sensor MITSUBISHI DIAMANTE 1900 Manual PDF
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1900, Model line: DIAMANTE, Model: MITSUBISHI DIAMANTE 1900Pages: 408, PDF Size: 71.03 MB
Page 170 of 408
DRIVEABILITYAND EMISSIONS CONTROLS 4-27
WITHOUTASCANTOOL
8 See Figure 87. 1. Remove the under dash cover, if equipped.
2. Attach an analoa voltmeter between the on-
board diagnostic outpit terminal of the data link con-
nector and the ground terminal
3. Turn the ignition switch ON.
4. Read the on-board diagnostic output pattern
from the voltmeter and record.
5. Diagnose and repair the faulty components as
required.
OBD OUTPUT
[TERMINAL
tic (OBO) output and ground terminal loca-
tions on the data link connector
6. Erase the trouble code.
7. Turn the ignition swatch ON, and read the di-
agnostic trouble codes, checking that a normal code
is output.
*To erase diagnostic trouble codes with a
scan tool, follow the directions given by the
tools manufacturer.
1. Turn the ignition switch OFF. 2. Disconnect the negative battery cable from the
battery for 1 minute or more, then reattach it.
3. Turn ON the ignition switch and read the diag-
nostic trouble codes checking that a normal code is
output.
Code 11 Oxygen sensor Code 12 Air flow sensor Code 13 Intake Air Temperature Sensor Code 14 Throttle Position Sensor (TPS) Code 15 SC Motor Position Sensor (MPS)
Code 21 Engine Coolant Temperature Sensor Code 22 Crank angle sensor Code 23 No. 1 cylinder TDC (camshaft position)
Sensor
Code 24 Vehicle speed sensor Code 25 Barometric pressure sensor Code 31 Knock sensor (KS) Code 32 Manifold pressure sensor Code 36 Ignition timmg adjustment signal Code 39 Oxygen sensor (rear - turbocharged) Code 41 Injector Code 42 Fuel pump Code 43 EGR-California Code 44 Ignition Coil; power transistor unit (No.
1 and No. 4 cvlinders) on 3.OL
Code 62 ignition Coil; power transistor unit (No.
2 and No. 5 cvlinders) on 3.OL
Code 53 ignition Coil; power transistor unit (No.
3 and No. 6 cylinders) on 3.OL
Code 55 AC valve position sensor Code 59 Heated oxygen sensor Code 61 Transaxle control unit cable (automatic
transmission)
Code 62 Warm-up control valve position sensor
(non-turbo)
The Powertrain Control Module (PCM) is given
responsibrlity for the operation of the emission con-
trol devices, cooling fans, ignition and advance and
in some cases, automatic transaxle functions. Be-
cause the PCM oversees both the ignition timing and
the fuel injection operation, a precise air/fuel ratio
will be maintained under all operating conditions,
The PCM is a microprocessor, or small computer,
which receives electrical inputs from several sensors,
switches and relays on and around the engine.
Based on combinations of these inputs, the PCM
controls outputs to various devices concerned with
engine operation and emissions. The control module
relies on the signals to form a correct picture of cur-
rent vehicle operation. If any of the input signals is
incorrect, the PCM reacts to whatever picture is
painted for it. For example, if the coolant temperature
sensor is inaccurate and reads too low, the PCM may
see a picture of the engine never warming up. Conse-
quently, the engine settings will be maintained as if
the engine were cold. Because so many inputs can
affect one output, correct diagnostic procedures are
essential on these systems,
One part of the PCM is devoted to monitoring
both input and output functions within the system.
This ability forms the core of the self-diagnostic sys-
tem. If a problem is detected within a circuit, the con-
trol module will recognize the fault, assign it a Diag-
nostic Trouble Code (DTC), and store the code in
memory. The stored code(s) may be retrieved during
diagnosis. While the OBD-II system is capable of recognizing
many internal faults, certain faults WIII not be recog-
nized. Because the control module sees only electri-
cal signals, it cannot sense or react to mechanical or
vacuum faults affecting engine operation. Some of
these faults may affect another component which will
set a code. For example, the PCM monitors the out-
put signal to the fuel injectors, but cannot detect a
partially clogged injector. As long as the output dri-
ver responds correctly, the computer will read the
system as functioning correctly. However, the im-
proper flow of fuel may result in a lean mixture. This
would, in turn, be detected by the oxygen sensor and
noticed as a constantly lean signal by the PCM. Once
the signal falls outside the pre-programmed limits,
the control module would notice the fault and set a
trouble code.
Additionally, the OBD-II system employs adaptive
fuel logic. This process is used to compensate for
normal wear and variability within the fuel system.
Once the engine enters steady-state operation, the
control module watches the oxygen sensor signal for
a bias or tendency to run slightly rich or lean. If such
a bias is detected, the adaptive logic corrects the fuel
delivery to bring the air/fuel mixture towards a cen-
tered or 14.7:1 ratio. This compensating shift is
stored In a non-volatile memory which is retained by
battery power even with the ignition switched
OFF. The correction factor is then available the next time
the vehicle is operated.
WITHASCANTOOL
8 See Figures 88, 89, 90, and 91
The Diagnostic Link Connector (DLC), under the
left-hand side of the instrument panel, must be lo-
cated to retrieve any OTC’s
Reading the control module memory is on of the
first steps in OBD II system diagnostics. This step
should be initially performed to determine the general
nature of the fault. Subsequent readings will deter-
mine if the fault has been cleared.
Reading codes can be performed by any of the
methods below:
l Read the control module memory with the
Generic Scan Tool (GST)
l Read the control module memory with the ve-
hicle manufacturers specific tester
To read the fault codes, connect the scan tool or
tester according to the manufacturers instructions.
Follow the manufacturers specified procedure for
reading the codes.
WITHOUTASCANTOOL
8 See Figure 92
The Diagnostic Link Connector (DLC), under the
left-hand side of the instrument panel, must be lo-
cated to retrieve any DTC’s.
Page 172 of 408
DRIVEABILITYAND EMISSIONS CONTROLS 4-29
PO108 Manifold Absolute Pressure/Barometric
Pressure Circuit High Input
PO109 Manifold Absolute Pressure/Barometric
Pressure Circuit Intermittent
PO110 intake Air Temperature Circuit Malfunction
PO111 Intake Air Temperature Circuit Range/Per-
formance Problem
PO112 Intake Air Temperature Circuit Low Input
PO113 Intake Air Temoerature Circuit Hiah lnout
PO114 Intake Air Temberature Circuit lnt&miitent
PO115 Engine Coolant Temperature Circuit Mal-
function -
PO116 Engine Coolant Temperature Circuit
Range/Performance Problem
PO117 Engine Coolant Temperature Circuit Low
Input
PO118 Engine Coolant Temperature Circuit High
Input
PO119 Engine Coolant Temperature Circuit Inter-
mittent
PO120 Throttle Position Sensor/Switch “A” Cir-
cuit Malfunction
PO121 Throttle Position Sensor/Switch “A” Cir-
cuit Range/Performance Problem
PO122 Throttle Position Sensor/Switch “A” Cir-
cuit Low Input
PO123 Throttle Position Sensor/Switch “A” Cir-
cuit High Input
PO124 Throttle Position Sensor/Switch “A” Cir-
cuit Intermittent
PO125 Insufficient Coolant Temperature For
Closed Loop Fuel Control
PO126 Insufficient Coolant Temperature For Sta-
ble Operation
PO130 02 Circuit Malfunction (Bank no. 1 Sen-
sor no. 1)
PO131 02 Sensor Circuit Low Voltage (Bank no.
1 Sensor no. 1)
PO132 02 Sensor Circuit High Voltage (Bank no.
1 Sensor no. 1)
PO133 02 Sensor Circuit Slow Response (Bank
no. 1 Sensor no. 1)
PO134 02 Sensor Circuit No Activity Detected
(Bank no. 1 Sensor no. 1)
PO135 02 Sensor Heater Circuit Malfunction
(Bank no. 1 Sensor no. 1)
PO136 02 Sensor Circuit Malfunction (Bank no.
1 Sensor no. 2)
PO137 02 Sensor Circuit Low Voltage (Bank no.
1 Sensor no. 2)
PO138 02 Sensor Circuit High Voltage (Bank no.
1 Sensor no. 2)
PO139 02 Sensor Circuit Slow Response (Bank
no. 1 Sensor no. 2)
PO140 02 Sensor Circuit No Activity Detected
(Bank no. 1 Sensor no. 2)
PO141 02 Sensor Heater Circuit Malfunction
(Bank no. 1 Sensor no. 2)
PO142 02 Sensor Circuit Malfunction (Bank no.
1 Sensor no. 3)
PO143 02 Sensor Circuit Low Voltage (Bank no.
1 Sensor no. 3)
PO144 02 Sensor Circuit High Voltage (Bank no.
1 Sensor no. 3)
PO145 02 Sensor Circuit Slow Response (Bank
no. 1 Sensor no. 3)
PO146 02 Sensor Circuit No Activity Detected
(Bank no. 1 Sensor no. 3)
PO147 02 Sensor Heater Circuit Malfunction
(Bank no. 1 Sensor no. 3)
PO150 02 Sensor Circuit Malfunction (Bank no.
2 Sensor no. 1) PO151 02 Sensor Circuit Low Voltage (Bank no.
2 Sensor no. 1)
PO152 02 Sensor Circuit High Voltage (Bank no.
2 Sensor no. 1)
PO153 02 Sensor Circuit Slow Response (Bank
no. 2 Sensor no. 1)
PO154 02 Sensor Circuit No Activity Detected
(Bank no. 2 Sensor no. 1)
PO155 02 Sensor Heater Circuit Malfunction
(Bank no. 2 Sensor no. 1)
PO156 02 Sensor Circuit Malfunction (Bank no.
2 Sensor no. 2)
PO157 02 Sensor Circuit Low Voltage (Bank no.
2 Sensor no. 2)
PO158 02 Sensor Circuit High Voltage (Bank no.
2 Sensor no. 2)
PO159 02 Sensor Circuit Slow Response (Bank
no. 2 Sensor no. 2)
PO160 02 Sensor Circuit No Activity Detected
(Bank no. 2 Sensor no. 2)
PO161 02 Sensor Heater Circuit Malfunction
(Bank no. 2 Sensor no. 2)
PO162 02 Sensor CircuitMalfunction(8ank
no.2 Sensorno.3)
PO16302 Sensor Circuit Low Voltage
(Bankno. Sensorno.3)
PO16402 Sensor Circuit HighVoltage
(Bankno. Sensorno.3)
PO16502 Sensor Circuit Slow Response
(Bankno. Sensorno.3)
PO166 02 Sensor Circuit No Activity De-
tected(Bankno.2 Sensorno.3)
PO16702 SensorHeaterCircuitMalfunc-
tion(Bank no.2 Sensorno.3)
PO170 Fuel Trim Malfunction (Bank no. 1 )
PO171 System Too Lean (Bank no. 1 )
PO172 Svstem Too Rich (Bank no 1 )
PO173 F;el Trim Malfundtion (Bank io. 2 )
PO174 System Too Lean (Bank no 2 )
PO175 System Too Rich (Bank no. 2 )
PO176 Fuel Composition Sensor Circuit Mal-
function
PO177 Fuel Composition Sensor Circuit
Range/Performance
PO178 Fuel Composition Sensor Circuit Low In-
put
PO179 Fuel Composition Sensor Circuit High In-
put
PO180 Fuel Temperature Sensor “A” Circuit Mal-
function
PO181 Fuel Temperature Sensor “A” Circuit
Range/Performance
PO182 Fuel Temperature Sensor “A” Circuit Low
Input
PO183 Fuel Temperature Sensor “A” Circuit High
Input
PO184 Fuel Temperature Sensor “A” Circuit Inter-
mittent
PO185 Fuel Temperature Sensor “B” Circuit Mal-
function
PO186 Fuel Temperature Sensor “B” Circuit
Range/Performance
PO187 Fuel Temperature Sensor “B” Circuit Low
Input
PO188 Fuel Temperature Sensor “B” Circuit High
Input
PO189 Fuel Temperature Sensor “B” Circuit Inter-
mittent
PO190 Fuel Rail Pressure Sensor Circuit Mal-
funchon
PO191 Fuel Rail Pressure Sensor Circuit
Range/Performance PO192 Fuel Rail Pressure Sensor Circuit Low In-
put
PO193 Fuel Rail Pressure Sensor Circuit High In-
put
PO194 Fuel Rail Pressure Sensor Circuit Intermit-
tent
PO195 Engine Oil Tempetature Sensor Malfunc-
tion
PO198 Engine Oil Temperature Sensor
Range/Performance
PO197 Engine Oil Temperature Sensor Low
PO198 Engine Oil Temperature Sensor High
W199 Engine Oil Temperature Sensor Intermit-
tent
PO200 Injector Circuit Malfunction
PO201 Injector Circuit Malfunction-Cylinder
no. 1
PO202 Injector Circuit Malfunction-Cylinder
no. 2
PO203 Injector Circuit Malfunction-Cylinder
no. 3
PO204 Injector Circuit Malfunction-Cylinder
no. 4
PO205 Injector Circuit Malfunction-Cylinder
no. 5
PO206 Injector Circuit Malfunction-Cylinder
no. 6
PO214 Cold Start Injector no. 2 Malfunction
PO215 Engine Shutoff Solenoid Malfunction
PO218 Injection Timing Control Circuit Malfunc-
tion
PO217 Engine Over Temperature Condition
PO218 Transmission Over Temperature Condition
PO219 Engine Over Speed Condition
PO220 Throttle Position Sensor/Switch ‘9” Cir-
cuit Malfunction
PO221 Throttle Position Sensor/Switch “B” Cir-
cuit Range/Performance Problem
PO222 Throttle Position Sensor/Switch “B” Cir-
cuit Low Input
PO223 Throttle Position Sensor/Switch “B” Cir-
cuit High Input
PO224 Throttle Position Sensor/Switch “B” Cir-
cuit Intermittent
PO225 Throttle Position Sensor/Switch “C” Cir-
cuit Malfunction
PO226 Throttle Position Sensor/Switch “C” Cir-
cuit Range/Performance Problem
PO227 Throttle Position Sensor/Switch “c” Cir-
cuit Low Input
PO228 Throttle Position Sensor/Switch “C” Cir-
cuit High Input
PO229 Throttle Position Sensor/Switch “C” Cir-
cuit Intermittent
PO230 Fuel Pump Primary Circuit Malfunction
PO231 Fuel Pump Secondary Circuit Low
PO232 Fuel Pump Secondary Circuit High
PO233 Fuel Pump Secondary Circuit Intermittent
PO261 Cylinder no. 1 Injector Circuit Low
PO262 Cylinder no. 1 Injector Circuit High
PO263 Cylinder no. 1 Contribution/Balance Fault
PO264 Cvlinder no. 2 lniector Circuit Low
PO265 Cylinder no. 2 Injector Circuit High
PO266 Cylinder no. 2 Contribution/Balance Fault
PO267 Cylinder no. 3 Injector Circuit Low
PO268 Cylinder no. 3 Injector Circuit High
PO269 Cylinder no. 3 Contribution/Balance Fault
PO270 Cylinder no. 4 Injector Circuit Low
PO271 Cvlinder no. 4 lniector Circuit Hiah
PO272 Cylinder no. 4 CbntributionlBalaice Fault
PO273 Cylinder no. 5 Injector Circuit Low
PO274 Cylinder no. 5 Injector Circuit High
Page 173 of 408
.
4-30 DRIVEABILITYAND EMISSIONS CONTROLS
PO275 Cvlinder no. 5 Contribution/Balance Fault
PO276 Cylinder no. 6 Injector Circuit Low
PO277 Cylinder no. 6 lniector Circuit High
PO278 Cylinder no. 6 Contribution/Balance Fault
PO300 Random/Multiple Cylinder Misfire De-
tected
PO301 Cylinder no. l-Misfire Detected
PO302 Cvlinder no 2-Misfire Detected
PO303 Cylinder no. 3-Misfire Detected
PO304 Cylinder no. 4-Misfire Detected
PO305 Cylinder no. +-Misfire Detected
PO306 Cylinder no. &-Misfire Detected
PO320 Ignition/Distributor Engine Speed Input
Circuit Malfunction
PO321 Ignition/Distributor Engine Speed Input
Circuit Range/Performance
PO322 Ignibon/Distributor Engine Speed Input
Circuit No Signal
PO323 Ignition/Distributor Engine Speed Input
Circuit Intermittent
PO325 Knock Sensor no. l-Circuit Malfunction
(Bank no. 1 or Single Sensor)
PO326 Knock Sensor no. l-Circuit Range/Per-
formance (Bank no. 1 or Srngle Sensor)
PO327 Knock Sensor no. l-Circuit Low Input
(Bank no. 1 or Single Sensor)
PO328 Knock Sensor no. l-Circuit High Input
(Bank no. 1 or Single Sensor)
PO329 Knock Sensor no. l-Circuit Input Inter-
mittent (Bank no. 1 or Smgle Sensor)
PO330 Knock Sensor no. 2-Circuit Malfunction
(Bank no. 2 )
PO331 Knock Sensor no. 2-Circuit Range/Per-
formance (Bank no. 2 )
PO332 Knock Sensor no. 2-Circuit Low Input
(Bank no. 2 )
PO333 Knock Sensor no. 2-Circuit High Input
(Bank no. 2 )
PO334 Knock Sensor no. 2-Circuit Input Inter-
mittent (Bank no. 2)
PO335 Crankshaft Position Sensor “A” Circuit
Malfunction
PO336 Crankshaft Position Sensor “A” Circuit
Range/Performance
PO337 Crankshaft Position Sensor “A” Circuit
Low Input
PO338 Crankshaft Position Sensor “A” Circuit
High Input
PO339 Crankshaft Position Sensor “A” Circuit In-
termittent
PO340 Camshaft Position Sensor Circuit Mal-
function
PO341 Camshaft Position Sensor Circuit
Range/Performance
PO342 Camshaft Position Sensor Circuit Low In-
put
PO343 Camshaft Position Sensor Circuit High In-
put
PO344 Camshaft Position Sensor Circuit Inter-
mittent
PO350 Ignition Coil Primary/Secondary Circuit
Malfunction
PO351 Ignition Coil “A” Primary/Secondary Cir-
cuit Malfunction
PO352 Ignition Coil “B” Primary/Secondary Cir-
cuit Malfunction
PO353 Ignition Coil “C” Primary/Secondary Cir-
cuit Malfunction
PO354 Ignition Coil “D” Primary/Secondary Cir-
cuit Malfunction
PO355 Ignition Coil “E” Primary/Secondary Cir-
cuit Malfunction PO356 Ignition Coil “F” Primary/Secondary Cir-
cuit Malfunction
PO357 Ignition Coil “G” Primary/Secondary Cir-
cuit Malfunction
PO358 Ignition Coil ‘Y-l” Primary/Secondary Cir-
cuit Malfunctron
PO359 Ignition Coil “I” Primary/Secondary Cir-
cuit Malfunction
PO360 Ignition Coil “J” Primary/Secondary Cir-
cuit Malfunction
PO361 Ignition Coil “K” Primary/Secondary Cir-
cuit Malfunction
PO362 Ignition Coil “L” Primary/Secondary Cir-
cuit Malfunction
PO370 Timing Reference High Resolution Signal
“A” Malfunction
PO371 Timing Reference High Resolution Signal
“A” Too Many Pulses
PO372 Timing Reference High Resolution Signal
“A” Too Few Pulses
PO373 Timing Reference High Resolution Signal
“A” Intermittent/Erratic Pulses
PO374 Timing Reference High Resolution Signal
“A” No Pulses
PO375 Timing Reference High Resolution Signal
“B” Malfunction
PO376 Timing Reference High Resolution Signal
“B” Too Many Pulses
PO377 Timing Reference High Resolution Signal
9” Too Few Pulses
PO378 Timing Reference High Resolution Signal
“B” Intermittent/Erratic Pulses
PO379 Timing Reference High Resolution Signal
“B” No Pulses
PO385 Crankshaft Position Sensor 9” Circuit
Malfunction
PO386 Crankshaft Position Sensor “B” Circuit
Range/Performance
PO387 Crankshaft Position Sensor ‘9” Circuit
Low Input
PO388 Crankshaft Position Sensor “B” Circuit
High Input
PO389 Crankshaft Position Sensor “B” Circuit In-
termittent
PO400 Exhaust Gas Recirculation Flow Malfunc-
tion
PO401 Exhaust Gas Recirculation Flow Insuffi-
cient Detected
PO402 Exhaust Gas Recirculation Flow Excessive
Detected
PO403 Exhaust Gas Recirculation Circuit Mal-
function
PO404 Exhaust Gas Recirculation Circuit
Range/Performance
PO405 Exhaust Gas Recirculation Sensor “A” Cir-
cuit Low
PO406 Exhaust Gas Recirculation Sensor “A” Cir-
cuit High
PO407 Exhaust Gas Recirculation Sensor “B” Cir-
cuit Low
PO408 Exhaust Gas Recirculation Sensor “B” Cir-
cuit High
PO410 Secondary Air Injection System Malfunc-
tion
PO411 Secondary Air Injection System Incorrect
Flow Detected
PO412 Secondary Air Injection System Switching
Valve “A” Circuit Malfunction
PO413 Secondary Air Injection System Switching
Valve “A” Circuit Open
PO414 Secondary Air Injection System Switching
Valve “A” Circuit Shorted PO415 Secondary Air Injection System Switching
Valve “B” Circuit Malfunction
PO416 Secondary Air Injection System Switching
Valve “B” Circuit Open
PO417 Secondary Air Injection System Switching
Valve “B” Circuit Shorted
PO418 Secondary Air Injection System Relay “A
Circuit Malfunction
PO419 Secondary Air Injection System Relay “B”
Circuit Malfunction
PO420 Catalyst System Efficiency Below Thresh-
old (Bank no. 1 )
PO421 Warm Up Catalyst Efficiency Below
Threshold (Bank no. 1 )
PO422 Main Catalyst Efficiency Below Threshold
(Bank no. 1 )
PO423 Heated Catalyst Efficiency Below Thresh-
old (Bank no. 1 )
PO424 Heated Catalyst Temperature Below
Threshold (Bank no. 1)
PO430 Catalyst System Efficiency Below Thresh-
old (Bank no. 2 )
PO431 Warm Up Catalyst Efficiency Below
Threshold (Bank no. 2 )
PO432 Main Catalyst Efficiency Below Threshold
(Bank no. 2)
PO433 Heated Catalyst Efficiency Below Thresh-
old (Bank no. 2 )
PO434 Heated Catalvst Temoerature Below
Threshold (Bank no. 2
j ’
PO440 Evaporative Emission Control System
Malfunction
PO441 Evaporative Emission Control System In-
correct Purge Flow
PO442 Evaporative Emission Control System
Leak Detected (Small Leak)
PO443 Evaporative Emission Control System
Purge Control Valve Circuit Malfunction
PO444 Evaporative Emission Control System
Purge Control Valve Circuit Open
PO445 Evaporative Emission Control System
Purge Control Valve Circuit Shorted
PO446 Evaporative Emission Control System
Vent Control Circuit Malfunction
PO447 Evaporative Emission Control System
Vent Control Circuit Open
PO448 Evaporative Emission Control System
Vent Control Circuit Shorted
PO449 Evaporative Emission Control System
Vent Valve/Solenoid Circuit Malfunction
PO450 Evaporative Emission Control System
Pressure Sensor Malfunction
PO451 Evaporative Emission Control System
Pressure Sensor Range/Performance
PO452 Evaporative Emission Control System
Pressure Sensor Low Input
PO453 Evaporative Emission Control System
Pressure Sensor High Input
PO454 Evaporative Emission Control System
Pressure Sensor Intermittent
PO455 Evaporative Emission Control System
Leak Detected (Gross Leak)
PO460 Fuel Level Sensor Circuit Malfunction
PO461 Fuel Level Sensor Circuit Range/Perfor-
mance
PO462 Fuel Level Sensor Circuit Low Input
PO463 Fuel Level Sensor Circuit High Input
PO464 Fuel Level Sensor Circuit Intermittent
PO465 Purge Flow Sensor Circuit Malfunction
PO466 Purge Flow Sensor Circuit Range/Perfor-
mance
PO467 Purge Flow Sensor Circuit Low Input
Page 174 of 408
DRIVEABILITYAND EMISSIONSCONTROL-S 4-31
PO466 Purge Flow Sensor Circuit High Input
PO469 Purqe Flow Sensor Circuit Intermittent
PO470 Exhaust Pressure Sensor Malfunction
PO471 Exhaust Pressure Sensor Range/Perfor-
mance
PO472 Exhaust Pressure Sensor Low
PO473 Exhaust Pressure Sensor Hiah
PO474 Exhaust Pressure Sensor lnirmittent
PO475 Exhaust Pressure Control Valve Malfunc-
tion
PO476 Exhaust Pressure Control Valve
Range/Performance
PO477 Exhaust Pressure Control Valve Low
PO476 Exhaust Pressure Control Valve High
PO479 Exhaust Pressure Control Valve Intermit-
tent
PO460 Cooling Fan no 1 Control Circuit Mal-
function
PO461 Cooling Fan no. 2 Control Circuit Mal-
function
PO462 Cooling Fan no. 3 Control Circuit Mal-
function
PO463 Cooling Fan Rationality Check Malfunc-
tion
PO464 Cooling Fan Circuit Over Current
PO465 Cooling Fan Power/Ground Circuit Mal-
function
PO500 Vehicle Speed Sensor Malfunction
PO501 Vehicle Speed Sensor Range/Performance
PO502 Vehicle Speed Sensor Circuit Low Input
PO503 Vehicle Speed Sensor Intermittent/Er-
ratic/High
PO505 Idle Control System Malfunction
PO506 Idle Control System RPM Lower Than Ex-
pected
PO507 Idle Control System RPM Higher Than Ex-
pected
PO510 Closed Throttle Position Switch Malfunc-
tion
PO520 Engine Oil Pressure Sensor/Switch Circuit
Malfunction
PO521 Engine Oil Pressure Sensor/Switch
Range/Performance
PO522 Engine Oil Pressure Sensor/Switch Low
Voltage
PO523 Engine Oil Pressure Sensor/Switch High
Voltage
PO530 A/C Refrigerant Pressure Sensor Circuit
Malfunction
PO531 A/C Refrigerant Pressure Sensor Circuit
Range/Performance
PO532 A/C Refrigerant Pressure Sensor Circuit
Low Input
PO533 A/C Refrigerant Pressure Sensor Circuit
High Input
PO534 A/C Refrigerant Charge Loss
PO550 Power Steering Pressure Sensor Circuit
Malfunction
PO551 Power Steering Pressure Sensor Circuit
Range/Performance
PO552 Power Steering Pressure Sensor Circuit
Low Input
PO553 Power Steering Pressure Sensor Circuit
High Input
PO554 Power Steering Pressure Sensor Circiit
Intermittent
PO560 System Voltage Malfunction
PO561 System Voltage Unstable
PO562 System Voltage Low
PO563 Svstem Voltaoe Hlah
PO565 Ciuise Control On%ignal Malfunction
PO566 Cruise Control Off Signal Malfunction PO567 Cruise Control Resume Signal Malfunc-
tion
PO566 Cruise Control Set Signal Malfunction
PO569 Cruise Control Coast Signal Malfunction
PO570 Cruise Control Accel Signal Malfunction
PO571 Cruise Control/Brake Switch “A” Circuit
Malfunction
PO572 Cruise Control/Brake Switch “A” Circuit
Low
PO573 Cruise Control/Brake Switch “A” Circuit
High
P0574Through PO560 Reserved for Cruise
Codes
PO600 Serial Communication Link Malfunction
PO601 Internal Control Module Memory Check
Sum Error
PO602 Control Module Programming Error
PO603 Internal Control Module Keep Alive Mem-
ory (KAM) Error
PO604 Internal Control Module Random Access
Memory (RAM) Error
PO605 Internal Control Module Read Only Mem-
ory (ROM) Error
PO606 PCM Processor Fault
PO606 Control Module VSS Output “A” Malfunc-
tion
PO609 Control Module VSS Output “6” Malfunc-
tion
PO620 Generator Control Circuit Malfunction
PO621 Generator Lamp “L” Control Circuit Mal-
function
PO622 Generator Field “F” Control Circuit Mal-
function
PO650 Malfunction Indicator Lamp (MIL) Control
Circuit Malfunctron
PO654 Engine RPM Output Circuit Malfunction
PO655 Engine Hot Lamp Output Control Circuit
Malfunction
PO656 Fuel Level Output Circuit Malfunction
PO700 Transmission Control System Malfunction
PO701 Transmission Control System Range/Per-
formance
PO702 Transmission Control System Electrical
PO703 Torque Converter/Brake Switch “B” Circuit
Malfunction
PO704 Clutch Switch Input Circuit Malfunction
PO705 Transmission Range Sensor Circuit Mal-
function (PRNDL Input)
PO706 Transmission Range Sensor Circuit
Range/Performance
PO707 Transmission Range Sensor Circuit Low
Input
PO706 Transmission Range Sensor Circuit High
Input
PO709 Transmission Range Sensor Circuit Inter-
mittent
PO710 Transmission FluId Temperature Sensor
Circuit Malfunction
PO711 Transmission Fluid Temperature Sensor
Circuit Range/Performance
PO712 Transmission Fluid Temperature Sensor
Circuit Low Input
PO713 Transmission Fluid Temperature Sensor
Circuit High Input
PO714 Transmission Fluid Temperature Sensor
Circuit Intermittent
PO715 Input/Turbine Speed Sensor Circuit Mal-
function
PO716 Input/Turbine Speed Sensor Circuit
Range/Performance
PO717 InpWurbine Speed Sensor Circuit No
Signal PO716 Inputflurbine Speed Sensor Circuit Inter-
mittent
PO719 Torque Converter/Brake Switch “B” Circuit
Low
PO720 Output Speed Sensor Circuit Malfunction
PO721 Output Speed Sensor Circuit Range/Per-
formance
PO722 Output Speed Sensor Circuit No Signal
PO723 Output Speed Sensor Circuit Intermittent
PO724 Toraue Converter/Brake Switch “B” Circuit
High
PO725 Engine Speed Input Circuit Malfunction
PO726 Engine Speed Input Circuit Range/Perfor-
PO727 Engine Speed Input Circuit No Signal
PO726 Engine Speed Input Circuit Intermittent
PO730 Incorrect Gear Ratio
PO731 Gear no. 1 Incorrect Ratio
PO732 Gear no. 2 Incorrect Ratio
PO733 Gear no. 3 Incorrect Ratio
PO734 Gear no 4 Incorrect Ratio
PO735 Gear no. 5 Incorrect Ratio
PO736 Reverse Incorrect Ratio
PO740 Torque Converter Clutch Circuit Malfunc-
tion
PO741 Torque Converter Clutch Circuit Perfor-
mance or Stuck Off
PO742 Torque Converter Clutch Circuit Stuck On
PO743 Torque Converter Clutch Circuit Electrical
PO744 Torque Converter Clutch Circuit Intermit-
tent
PO745 Pressure Control Solenoid Malfunction
PO746 Pressure Control Solenoid Performance or
Stuck Off
PO747 Pressure Control Solenoid Stuck On
PO746 Pressure Control Solenoid Electrical
PO749 Pressure Control Solenoid Intermittent
PO750 Shift Solenoid “A” Malfunction
PO751 Shift Solenoid “A” Performance or Stuck
Off
PO752 Shift Solenoid “A” Stuck On
PO753 Shift Solenoid “A” Electrical
PO754 Shift Solenoid “A” Intermittent
PO755 Shift Solenoid “8 Malfunction
PO756 Shift Solenoid “B” Performance or Stuck
Oft
PO757 Shift Solenoid “B” Stuck On
PO756 Shift Solenoid “6” Electrical
PO759 Shift Solenoid “8” Intermittent
PO760 Shift Solenoid “C” Malfunction
PO761 Shift Solenoid “C” Performance Or Stuck
Oft
PO762 Shift Solenoid “C” Stuck On
PO763 Shift Solenoid “C” Electrical
PO764 Shift Solenoid “C” Intermittent
PO765 Shift Solenoid “D” Malfunction
PO766 Shift Solenoid “D” Performance Or Stuck
Oft
PO767 Shift Solenoid “D” Stuck On
PO766 Shift Solenoid “D” Electrical
PO769 Shift Solenoid “D” Intermittent
PO770 Shift Solenoid “E” Malfunction
PO771 Shift Solenoid “E” Performance Or Stuck
Off
PO772 Shift Solenoid “E” Stuck On
PO773 Shift Solenoid “E” Electrical
PO774 Shift Solenoid “E” Intermittent
PO760 Shift Malfunction
PO761 l-2 Shift Malfunction
PO762 2-3 Shift Malfunction
PO763 3-4 Shift Malfunction
PO764 4-5 Shift Malfunction
Page 175 of 408
4-32 DRIVEABILITYAND EMISSIONS CONTROLS
PO785 Shift/Timing Solenoid Malfunction
PO786 Shift/Timing Solenoid Range/Performance
PO787 Shift/Timing Solenoid Low
PO788 Shift/Timing Solenord High
PO789 Shift/Timing Solenoid Intermittent
PO790 Normal/Performance Switch Circuit Mal-
function
PO801 Reverse Inhibit Control Circuit Malfunc-
tion
PO803 l-4 Upshift (Skip Shift) Solenoid Control
Circuit Malfunction
PO804 l-4 Upshift (Skip Shift) Lamp Control
Circuit Malfunction
PllOO Induction Control Motor Position Sensor
Fault
PI101 Traction Control Vacuum Solenoid Circuit
Fault
Pl102 Traction Control Ventilation Solenoid Cir-
cuit Fault P1294 Target Idle Speed Not Reached
P1295 No 5-Volt Supply To TP Sensor
P1296 No 5-Volt Supply To MAP Sensor
P1297 No Change In MAP From Start To Run
PI300 Ignition Timing Adjustment Circuit
Pl390 Timing Belt Skipped One Tooth Or More
Pl391 Intermittent Loss Of CMP Or CKP Sensor
Signals P1495 EVAP Ventilation Solenoid Circurt Fault
P1496 5-Volt Supply Output Too Low
Pl500 Generator FR Terminal Circuit Fault
Pl600 PCM-TCM Serial Communication Link
Circuit Fault
Pl400 Manifold Differential Pressure Sensor
Fault P1696 PCM Failure- EEPROM Write Denied
Pl715 No CCD Messages From TCM
Pl750 TCM Pulse Generator Circuit Fault
Pl791 Pressure Control, Shift Control, TCC So-
lenoid Fault
P1443 EVAP Purge Control Solenoid “2” Circuit
Fault P1899 PCM ECT Level Signal to TCM Circuit
Fault
P1486 EVAP Leak Monitor Pinched Hose De-
tected
P1989 High Speed Condenser Fan Control Relay
Fault
P1487 High Speed Radiator Fan Control Relay
Circuit Fault
Pl490 Low Speed Fan Control Relay Fault
P1492 Battery Temperature Sensor High Voltage
P1494 EVAP Ventilation Switch Or Mechanical
FLASH OUT CODE LIST
# See Figures
93, 94, 95, and 96
Fault PI105 Fuel Pressure Solenoid Circuit Fault
Code
Output pattern
(for voltmeter) Cause
P1702
Shorted throttle position sensor cil
cuit
MATOOSE
Pl701
Open throttle position sensor circuii
A!iATW5F
p1704 -
Throttle position sensor malfunc-
tion
Improperly adjusted throttle posi-
ASATmH tion sensor
PO71 2
Open fluid temperature sensor cir-
u 1 cuit
ASAT
PO71 3
Shorted fluid temperature sensor
circuit
ASATOOU
Pl709
I I Open kickdown servo switch circuit
Shorted kickdown servo switch cir-
cuit
A5ATOOSK
Remedy
o Check the throttle position sen-
sor connector
o check the throttle position sen-
sor itself
o Check the closed throttle posi-
tion switch
o Check the throttle position sen-
sor wiring harness
o Check the wiring between ECM
and throttle position sensor
o Fluid temperature sensor con-
nector inspection
o Fluid temperature sensor inspec-
tion
o Fluid temperature sensor wiring
harness inspection
o Check the kickdown servo switch
connector
o Check the kickdown servo switch
o Checkthe kickdown servo switch
wiring harness
Fig. 93 Mitsubishi flash out DTC's, 1 of 4-Type 4 (DBD II) Codes
Page 190 of 408
FUELSYSTEM 513
l Always replace worn fuel fitting O-rings with
new. Do not substitute fuel hose or equivalent, where
I
The Multi-Point Injection (MPI) system is electroni-
rally controlled by the Engine Control Module (ECM),
based on data from various sensors. The ECM controls
the fuel flow, idle speed and ignition timing. fuel pipe is installed.
Fuel is supplied to the injectors by an electric in-
tank fuel pump and is distributed to the respective in-
jectors via the main fuel pipe. The fuel pressure ap-
plied to the injector is constant and higher than the
pressure in the intake manifold. The pressure is con-
trolled by the fuel pressure regulator. The excess fuel
is returned to the fuel tank through the fuel return pipe.
When an electric current flows in the injector, the
injector valve is fully opened to supply fuel. Since the
fuel pressure is constant, the amount of the fuel in-
jetted from the injector into the manifold is increased
or decreased in proportion to the time the electric
current flows. Based on ECU signals, the injectors in-
ject fuel to the cylinder manifold ports in firing order. Fuel injection systems remain under pres-
sure after the engine has been turned OFF.
Properly relieve fuel pressure before discon-
neeting any fuel lines. Failure to do so may
result in fire or personal injury.
1. Turn the ignition to the OFF position.
2. Loosen the fuel filler cap to release fuel tank
pressure.
I
The flow rate of the air drawn through the air
cleaner is measured by the air flow sensor. The air
enters the air intake plenum or manifold through the
throttle body. In the intake manifold, the air is mixed
with the fuel from the injectors and is drawn into the
cylinder, The air flow rate is controlled according to
the degree of the throttle valve and the servo motor
openings. The system is monitored through a num-
ber of sensors which feed information on engine con-
ditions and requirements to the ECM. The ECM cal-
culates the injection time and rate according to the
signals from the sensors,
Safety is the most important factor when perform-
ing not only fuel system maintenance but any type of
maintenance. Failure to conduct maintenance and re-
pairs in a safe manner may result in serious personal
injury or death. Maintenance and testing of the vehi-
cle’s fuel system components can be accomplished
safely and effectively by adhering to the following
rules and guidelines.
l To avoid the possibility of fire and personal in-
jury, always disconnect the negative battery cable un-
less the repair or test procedure requires that battery
voltage be applied.
l Always relieve the fuel system pressure prior to
disconnecting any fuel system component (injector,
fuel rail, pressure regulator, etc.), fitting or fuel line
connection. Exercise extreme caution whenever re- Observe all applicable safety precautions
when working around fuel. Whenever servic-
ing the fuel system, always work in a well
ventilated area. Do not allow fuel spray or va-
pors to come in contact with a spark or open
flame. Keep a dry chemical fire extinguisher
near the work area. Always keep fuel in a con-
tainer specifically designed for fuel storage;
also, always properly seal fuel containers to
avoid the possibility of fire or explosion.
3. For the Mirage, Diamante, and 1994-00
Galant, remove the rear seat cushion, then remove
the service cover and detach the fuel pump harness
connector.
4. For the 1990-93 FWD Galant, detach the fuel
pump harness connector located in the area of the
fuel tank. It may be necessary to raise the vehicle to
access the connector.
5. For the 1990-93 AWD Galant, remove the car-
pet from the trunk, locate the fuel tank wiring at the
pump access cover, then detach the wiring.
6. Start the vehicle and allow it to run until it
stalls from lack of fuel. Turn the key to the OFF posi-
tion.
7. Disconnect the negative battery cable, then at-
tach the fuel pump connector. Install the access .
cover, cushion or carpet as necessary.
8. Wrap shop towels around the fitting that is be-
ing disconnected to absorb residual fuel in the lines.
9. Place shop towels into proper safety container. Fig, 8 Detach the connector for the throttle
position (TP) sensor
93153ps5 Fig, 9 Remove the accelerator cable end
from the throttle lever
Fig. IO Remove the hose shown here from
lieving fuel system pressure to avoid exposing skin,
face and eyes to fuel spray. Please be advised that
fuel under pressure may penetrate the skin or any
part of the body that it contacts.
l Always place a shop towel or cloth around the
fitting or connection prior to loosening to absorb any
excess fuel due to spillage. Ensure that all fuel
spillage (should it occur) is quickly removed from
enginesurfaces. Ensure that all fuel soaked cloths or
towels are deposited into a suitable waste container.
l Always keep a dry chemical (Class B) fire ex-
tinguisher near the work area.
l Do not allow fuel spray or fuel vapors to come
into contact with a spark or open flame.
l Always use a backup wrench when loosening’
and tightening fuel line connection fittings. This will
prevent unnecessary stress and torsion to fuel line
piping. Always follow the proper torque specifica-
tions. REMOVAL &INSTALLATION
p See Figures 8 thru 18
1. Properly relieve the fuel system pressure as
outlined earlier in this section.
2. Drain the engine cooling system into a suit-
able container.
3. Matchmark the jocation of the adjuster bolt
on the accelerator cable mounting flange. This will
assure that the cable is installed in its original loca-
tion. Remove the throttle cable adjusting bolt and
disconnect the cable from the lever on the throttle
body. Position cable aside.
Page 200 of 408
FUELSYSTiM 5-13
1. BODY HARNESS CONNECTION
2 HOSE CONNECTION
3 PURGE HOSE
4 VAPOR HOSE
5 VENT HOSE
6 FllLER HOSE
7 PIPE ASSEMBLY
8. BAND ASSEMBLY
9 FUEL TANK ASSEMBLY
10. DIFFERENTIAL PRESSURE
SENSOR
11 FUEL HARNESS
12 HIGH-PRESSURE FUEL HOSE 1; ;;JL RETURN HOSE
15 FUEL PUMP MODULE
16 FILLER NECK
17 FUEL CAP
IS REINFORCEMENT
19 PACKING
20 VAPOR HOSE
21 SEPARATOR ASSEMBLY
22 VAPOR HOSE
23 FUEL CHECK VALVE ASSEMBLY
24 FUEL FILLER NECK ASSEMBLY
Fig. 54 Fuel tank and related components-1999-00 Galant
:ia. 55 Fuel tank and related components-1992-96 Diamante
11. Align the 3 projections on packing with the
holes on the fuel pump and the nipples on the pump
facing the same direction as before removal.
12. Install the holdrng bolt through the bottom of
the tank. Make sure the gasket on the bolt is replaced
and is not pinched during installation. Torque to 10
ft. Ibs. (14 Nm).
1 PatkIng brake cable COnneCtlo” 11
2 Fuel tank “.qm hose
12 Fuel fllk, neck
3 “apot hose 13 Fuel filler assembly
4 Pressure hose 14
5 Vapor hose COnneCflOn Fuel p,pe
6 Fuel pump am gauge assembly
7 Vapor hose
8 Valve assembly
9 Fuel mer cap
10 FllkY hose
:ig. 56 Fuel tank and related components-1997-00 Diamante 93155g15
cal harness of the fuel gauge unit to allow for the fuel
pling. Lower the lateral rod and suspend from the
tank to be lowered slightly. If not, label and discon-
axle beam using wire.
nect the electrical harness at the fuel gauge unit.
6. Detach the high pressure fuel line connector 9. Remove the six retaining bolts and gasket
from the base of the tank.
at the pump.
10. Remove the fuel pump assembly.
7. Loosen self-lockinq nuts on tank suooort
To install: straps to the end of the stud bolts.
8 Remove the right side lateral rod attaching
bolt and drsconnect the arm from the right body cou- *If the packing material is damaged or de-
formed, replace it with new packing.
7923PG79 :ig. 57 Proper method of supporting real
rxhaust system-Diamante 3.01 engine
Page 205 of 408
6-2 CHASSIS ELECTRICAL
) See Figure 1
For any 12 volt, negative ground, electrical system
to operate, the electricity must travel in a complete
circurt. This simply means that current (power) from
the posibve (t) terminal of the battery must eventu-
ally return to the negative (-) terminal of the battery.
Along the way, this current will travel through wires,
fuses, switches and components. If, for any reason,
the flow of current through the circuit is interrupted,
the component fed by that circuit will cease to func-
tion properly.
Perhaps the easiest way to visualize a circuit is to
think of connecting a light bulb (with two wires at-
tached to it) to the battery-one wire attached to the
negative (-) terminal of the battery and the other wire
to the positive (t) terminal. With the two wires touch-
ing the battery terminals, the circuit would be com-
plete and the light bulb would illummate. Electricity
would follow a path from the battery to the bulb and
back to the battery. It’s easy to see that wrth longer
wires on our light bulb, it could be mounted any-
where. Further, one wire could be fitted with a switch
so that the light could be turned on and off.
The normal automotive circuit differs from this
simple example in two ways, Frrst, instead of having
a return wire from the bulb to the battery, the current
travels through the frame of the vehicle. Since the
negative (-) battery cable is attached to the frame
(made of electrically conductive metal), the frame of
the vehicle can serve as a ground wire to complete
the circuit. Secondly, most automotive circuits con-
tain multiple components which receive power from a
single circuit. This lessens the amount of wire
needed to power components on the vehicle.
HOW DOES ELECTRlClTYWORK:THE
WATER ANALOGY
Electricity is the flow of electrons-the subatomic
particles that constitute the outer shell of an atom.
Electrons spin in an orbit around the center core of
RETURN
RETURN
CONDUCTOR
CONDUCTOR
GROUND
GROUND
lccs2w
Fig. 1 This example illustrates a simple cir-
cuit. When the switch is closed, power from
the positive (t) battery terminal flows
through the fuse and the switch, and then
to the light bulb. The light illuminates and
the circuit is completed through the ground
wire back to the negative (-) battery termi-
nal. In reality, the two ground points shown
in the illustration are attached to the metal
frame of the vehicle, which completes the
circuit back to the battery
an atom The center core is comprised of protons
(positive charge) and neutrons (neutral charge). Elec-
trons have a negative charge and balance
out the
positive charge of the protons. When an outside force
causes the number of electrons to unbalance the
charge of the protons, the electrons will split off the
atom and look for another atom to balance out. If this
imbalance is kept up, electrons will continue to move
and an electrical flow will exist.
Many people have been taught electrical theory
using an analogy with water. In a comparison wrth
water flowing through a pipe, the electrons would be
the water and the wire is the pipe.
The flow of electricity can be measured much like
the flow of water through a pipe. The unit of measure-
ment used is amperes, frequently abbreviated as
amps (a). You can compare amperage to the volume
of water flowing through a pipe. When connected to a
circuit, an ammeter WIII measure the actual amount of
current flowing through the circuit. When relatively
few electrons flow through a circuit, the amperage is
low. When many electrons flow, the amperage is
high.
Water pressure is measured in units such as
pounds per square inch (psi); The electrical pressure
is measured in unrts called volts (v). When a volt-
meter is connected to a circuit, it is measuring the
electrical pressure.
The actual flow of electricity depends not only on
voltage and amperage, but also on the resistance of
the circuit The higher the resistance, the higher the
force necessary to push the current through the cir-
cuit. The standard unit for measuring resistance is an
ohm. Resistance in a crrcuit varies dependmg on the
amount and type of components used in the circuit.
The main factors which determine resistance are:
l Material-some materials have more resis-
tance than others Those with high resistance are said
to be insulators Rubber materials (or rubber-like
plashcs) are some of the most common insulators
used in vehicles as they have a very high resistance
to electricity Very low resistance materials are said to
be conductors. Copper wire is among the best con-
ductors. Silver is actually a superior conductor to
copper and is used in some relay contacts, but its
high cost prohibits its use as common wiring Most
automotive wiring is made of copper.
l Size-the larger the wire size being used, the
less resistance the wire will have. This IS why com-
ponents which use large amounts of electricity usu-
ally have large wires supplying current to them.
l Length-for a given thickness of wire, the
longer the wire, the greater the resistance. The
shorter the wire, the less the resistance. When deter-
mining the proper wire for a circuit, both size and
length must be considered to design a circuit that can
handle the current needs of the component.
l Temperature-with many materials, the higher
the temperature, the greater the resistance (positive
temperature coefficient). Some materials exhibit the
opposite trait of lower resistance with higher temper-
atures (negative temperature coefficient). These prin-
ciples are used in many of the sensors on the engine
OHM'S LAW
There is a direct relationship between current,
voltage and resistance. The relationship between cur- rent, voltage and resistance can be summed up by a
statement known as Ohm’s law.
Voltage (E) is equal to amperage (I) times resis-
tance (R): E=l x R
Other forms of the formula are R=E/I and I=E/R
In each of these formulas, E is the voltage in volts,
I is the current in amps and R IS the resistance in
ohms. The basic point to remember is that as the re-
sistance of a circuit goes up, the amount of current
that flows in the circuit will go down, if voltage re-
mains the same.
The amount of work that the electricity can perform
is expressed as power. The unit of power is the watt
(w). The relationship between power, voltage and
current
IS expressed as:
Power(w) is equal to amperage (I) times voltage
(E): W=l x E
This is only true for direct current (DC) circuits:
The alternating current formula is a tad different, but
since the electrical circuits in most vehicles are DC
type, we need not get into AC circuit theory.
POWERSOURCE
Power is supplied to the vehicle by two devices:
The battery and the alternator. The battery supplies
electrical power during starting or during periods
when the current demand of the vehicle’s electrical
system exceeds the output capacity of the alternator.
The alternator supplies electrical current when the
engine is running
Just not does the alternator supply
the current needs of the vehicle, but it recharges the
battery.
The Battery
In most modern vehicles, the battery is a lead/acid
electrochemical device consisting of six 2 volt sub-
sections (cells) connected in series, so that the unit
is capable of producing approximately 12 volts of
electrical pressure. Each subsection consists of a se-
ries of positive and negative plates held a short dis-
tance apart in a solutron of sulfuric acid and water.
The two types of plates are of dissimilar metals,
This sets up a chemrcal reaction, and it is this reac-
tion which produces current flow from the battery
when Its positive and negattve terminals are con-
nected to an electrical load. The power removed from
the battery is replaced by the alternator, restoring the
battery to its original chemical state.
The Alternator
On some vehicles there isn’t an alternator, but a
generator. The difference IS that an alternator sup-
plies alternating current which is then changed to di-
rect current for
use on the vehicle, while a generator
produces direct current. Alternators tend to be more
efficient and that is why they are used.
Alternators and generators are devices that consist
of coils of wires wound together making big electro-
magnets. One group of coils spins within another set
and the interaction of the magnetic fields causes a
current to flow. This current is then drawn off the
coils and fed into the vehicles electrical system.
Page 207 of 408
I
6-4 CHASSIS ELECTRICAL
I
printed circuit is sandwiched between two sheets of
plastic for more protection and flexibility. A complete l Weatherproof-these connectors are most the jumper wire is of too small a gauge, it
printed circuit, consisting of conductors, insulating commonly used where the connector is exposed to
may overheat and possibly melt. Never use
material and connectors for lamps or other compo- the elements. Terminals are protected against mois-
nents is called a printed circuit board. Printed cir- ture and dirt by sealing rings which provide a weath- jumpers to bypass high resistance loads in a
et-tight seal. All repairs require the use of a special circuit. Bypassing resistances, in effect, cre-
cuitry is used in place of individual wires or har- ates a short circuit. This may, in turn, cause
nesses in places where space is limited, such as terminal and the tool required to service it. Unlike
behind instrument panels. standard blade type terminals, these weatherproof damage and fire. Jumper wires should only
be used to bypass lengths of wire or to simu-
Since automotive electrical systems are very sen- terminals cannot be straightened once they are bent. late switches.
sitive to changes in resistance, the selection of prop- ‘Make certain that the connectors are properly seated
erly sized wires is critical when systems are repaired, and all of the sealing rings are in place when con-
netting leads. Jumper wires are simple, yet extremely valuable,
A loose or corroded connection or a replacement wire pieces of test equipment. They are basically test wires
that is too small for the circuit will add extra resis-
l Molded-these connectors require complete which are used to bypass sections of a circuit. Al-
replacement of the connector if found to be defective.
tance and an additional voltage drop to the circuit. though jumper wires can be purchased, they are usu-
The wire gauge number is an expression of the This means splicing a new connector assembly into ally fabricated from lengths of standard automotive
cross-section area of the conductor. Vehicles from the harness. All splices should be soldered to insure
proper contact. Use care when probing the connec- wire and whatever type of connector (alligator clip,
countries that use the metric system will typically de- spade connector or pin connector) that is required for
scribe the wire size as its cross-sectional area in tions or replacing terminals in them, as it is possible
square millimeters. In this method, the larger the to create a short circuit between opposite terminals. If the particular application being tested. In cramped,
hard-to-reach areas, it is advisable to have insulated
wire, the greater the number. Another common sys- this happens to the wrong terminal pair, it is possible
to damage certain components. Always use jumper boots over the jumper wire terminals in order to pre-
tern for expressing wire size is the American Wire vent accidental grounding. It is also advisable to in-
Gauge (AWG) system. As gauge number increases, wires between connectors for circuit checking and
NEVER probe through weatherproof seals. elude a standard automotive fuse in any jumper wire.
area decreases and the wire becomes smaller. An 18
gauge wire is smaller than a 4 gauge wire. A wire
l Hard Shell-unlike molded connectors, the This is commonly referred to as a “fused jumper”. By
inserting an in-line fuse holder between a set of test
terminal contacts in hard-shell connectors can be re-
with a higher gauge number will carry less current
placed. Replacement usually involves the use of a leads, a fused jumper wire can be used for bypassing :
than a wire with a lower gauge number. Gauge wire open circuits. Use a 5 amp fuse to provide protection
size refers to the size of the strands of the conductor, special terminal removal tool that depresses the lock- against voltage spikes.
not the size of the complete wire with insulator. It is ing tangs (barbs) on the connector terminal and al-
lows the connector to be removed from the rear of the Jumper wires are used primarily to locate open
possible, therefore, to have two wires of the same
shell. The connector shell should be replaced if it electrical circuits, on either the ground (-) side of the
gauge with different diameters because one may have
thicker insulation than the other. shows any evidence of burning, melting, cracks, or circuit or on the power (+) side. If an electrical corn-
breaks. Replace individual terminals that are burnt, ponent fails to operate, connect the jumper wire be-
It is essential to understand how a circuit works
corroded, distorted or loose. tween the component and a good ground. If the corn-
before trying to figure out why it doesn’t. An electrical ponent operates only with the jumper installed, the
schematic shows the electrical current paths when a ground circuit is open. If the ground circuit is good,
circuit is operating properly. Schematics break the but the component does not operate, the circuit be-
entire electrical system down into individual circuits. tween the power feed and component may be open. ’
In a schematic, usually no attempt is made to repre- Pinpointing the exact cause of trouble in an elec- By moving the jumper wire successively back from
trical circuit is most times accomplished by the use the component toward the power source, you can
; : sent wiring and components as they physically ap-
pear on the vehicle; switches and other components of special test equipment. The following describes isolate the area of the circuit where the open is lo-
are shown as simply as possible. Face views of har- different types of commonly used test equipment and cated. When the component stops functioning, or the f
j
ness connectors show the cavity or terminal locations briefly explains how to use them in diagnosis. In ad- power is cut off, the open is in the segment of wire j
in all multi-pin connectors to help locate test points. dition to the information covered below, the tool between the jumper and the point previously tested.
! manufacturer’s instructions booklet (provided with You can sometimes connect the jumper wire di-
the tester) should be read and clearly under.$ood be- rectly from the battery to the “hot” terminal of the I
CONNECTORS 1 fore attempting any test procedures. component, but first make sure the component uses 1
# See Figures 5 and 6 JUMPER WIRES 12 volts in operation. Some electrical components, i
such as fuel injectors or sensors, are designed to op-
Three types of connectors are commonly used in erate on about 4 to 5 volts, and running 12 volts di- j
)
automotive applications-weatherproof, molded and rectly to these components will cause damage.
hard shell.
Never use jumper wires made from a thinner TEST LIGHTS I
gauge wire than the circuit being tested. If
# See Figure 7
The test light is used to check circuits and compo-
I nents while electrical current is flowing through
Fig. 5 Hard shell (left) and weatherproof
(right) connectors have replaceable termi- Fig. 7 A 12 volt test light is used to di%
nals
ements 1 the presence of voltage in a circuit
Page 209 of 408
.
6-6 CHASSIS ELECTRICAL
This test already assumes the existence of an open
in the circuit and it is used to help locate the open
portion
1. Isolate the circuit from power and ground.
2. Connect the self-powered test light or ohmme-
ter ground clip to the ground side of the circuit and
probe sections of the circuit sequentially.
3. If the light is out or there is infinite resistance,
the open is between the probe and the circuit ground.
4. If the light is on or the meter shows continuity,
the open is between the probe and the end of the cir-
cuit toward the power source.
SHORT CIRCUITS
*Never use a self-powered test tight to per-
form checks for opens or shorts when power Fig. 10 Checking the resistance of a coolant
temperature sensor with an ohmmeter.
Reading is 1.04 kilohms
is applied to the circuit under test. The test
linht man he dmn~nsrl hu nutnitls nnuva~ if there is more than one load in the circuit, since all m.3.m. “Y.. “1 “ulll”y”” u, ““..7IYG p”“lz’.
1. Isolate the circuit from power and ground.
2. Connect the self-powered ’ .,.*. ,
ted ugnt or onmme-
ter ground clip to a good ground
and probe any easy-
to-reach point in the circuit.
3. If the light comes on or there is continuity,
there is a short somewhere in the circuit.
4. To isolate the short, probe a test point at either
end of the isolated circuit (the light should be on or
the meter should indicate continuity).
5. Leave the test light probe engaged and se- voltage drops are cumulative.
1. Set the voltmeter selector switch to the 20 volt
^,.^X^..
pJbl1IUII.
2. Connect the multimeter negative lead to a
good ground.
3. Operate the circuit and check the voltage prior
.
to the hrst component (load).
4. There should be little or no voltage drop in the
circuit prior to the first component. If a voltage drop
exists, the wire or connectors in the circuit are sus-
WY.+
)JGW 5. While operating the first component in the cir-
.
positive meter lead and observe the voltage readings.
A small voltage drop should be noticed. This voltage
drop is caused by the resistance of the component.
6. Repeat the test for each component (load)
de .-IL- .‘.. .I
uuwn me crrcun. quentially open connectors or switches, remove
parts, etc. until the light goes out or continuity is bro-
ken
6. When the light goes out, the short is between
the last two circuit components which were opened,
nl -r*l?I-
VuLlHbt
This test determines voltage available from the
battery and should be the first step in any electrical
troubleshooting procedure after visual inspection,
Many electrical problems, esoeciallv on comouter
controlled systems, can be caused by a low state of 7. If a large voltage drop is noticed, the preceding
component, wire or connector is suspect.
# See Figures
10 and 11
charge in the battery. Excessive corrosion at the bat-
tery cable terminals can cause poor contact that will
prevent proper charging and full battery current flow,
1. Set the voltmeter selector switch to the 20V
position.
2. Connect the multimeter negative lead to the
h*+tnn,‘n nnn,,,;~,,. , ..^,a ^-L.--:^^l --_I ‘I- ---!I?... Never use an ohmmeter with power applied
to the circuit. The ohmmeter is designed to
operate on its 0 wn power supply. The normal
1^
. . . . . Fig. 11 Spark plug wires can be checke;
MW~ 3 IlG~dllYt: t-1 pUSI UI Lellllllldl allU lilt, pUSlIlVe lead to the battery’s positive (t) post or terminal.
3. Turn the ignition switch ON to provide a load,
4. A well charged battery should register over 12
volts. If the meter reads below 11 5 vnlts tha hq*anr
_ _ .-, . power may be insufficient to operate the eler ii! volt electrical system voltage could dam-
age the meter!
1. Isolate the circuit from the vehicle’s power
CnlOrAn I)““IW. 2. Ensure that the ignition key is OFF when dis- Almost anyone can replace damaged wires, as
long as the proper tools and parts are available. Wire
and terminals are available to fit almost any need.
Even the specialized weatherproof, molded and hard
shell connectors are now cl mdicm available from aftermarket
system properly.
connecting any components or the battery. ““yp,8w’“.
3. Where necessary, also isolate at least one side Be sure the ends of all the wires are fitted with the
VOLTAGEDROP of the circuit to be checked, in order to avoid reading proper terminal hardware and connectors. Wrapping
parallel resistances. Parallel circuit resistances will a wire around a stud is never a permanent solution
# See Figure 9 always give a lower reading than the actual resistance and will only cause trouble later. Replace wires one at
When current flows through a load, the voltage be- of eifhy n< +hn hmnnh-r
GI “I II It: “I a lb1 It?>. a time to avoid confusion. Always route wires exactly
4.
Connect the meter leads to both sides of the the same as the factory.
yond the load drops. This voltage drop is due to the
resistance created by the load and also by small re- circuit (wire or component) and read the actual mea-
sured ohms on the meter scale. Make sure the selec- *If connector repair is necessary, only at-
sistances created by corrosion at the connectors and
tor switch is set to the proper ohm scale for the cir- tempt it if you have the proper tools. Weath-
damaged insulation on the wires. The maximum al- erproof and hard shell connectors require
lowable voltage drop under load is critical, especially cuit being tested, to avoid misreading the ohmmeter
test value. spectal tools to release the pins inside the
connector. Attempting to repair these con-
nectors with conventional hand tools will
damage them.