ABS ISUZU TF SERIES 2004 Workshop Manual
Page 2571 of 4264
STARTING AND CHARGING SYSTEM 6D3-17
fan.
4. Replacing the brushes (inbuilt regulator)
Check the brushes for length, this is measured from the brush
holder to the end of the brush along it's centre line. Also
inspect for any sideways wear. If worn replace both brushes.
The minimum length is 3.8mm. Inspect the brush springs for
signs of corrosion or loss of tension or uneven tension.
Replacing the brushes, using a soldering iron apply heat to the
soldered joints on the rear of the brush holder of the regulator,
using a small lever prise up the retaining tabs to release the
brush lead and spring. Thread the new brush lead up the
brush holder along with the spring, pull the lead through the
tabs until the brush is protruding 12mm from the holder.
Bend down the tabs and solder the brush lead taking care not
to allow the solder to run up the lead which will reduce
flexibility. Use 60/40 resin cored solder.
5. Ball bearing
Please note the bearings used in this KCA generator are a
high
tolerance type, only fully sealed bearings of the same
specification are to be used as replacements. It is
recommended that the bearings be replaced during the
reconditioning process to restore the unit to original
specification.
6. Regulator
The regulator can only be tested when fitted into an altenator.
Warning: do not reverse"S" and "L" connections or put 12
volt supply to "L" terminal, this connection must not be
used as a supply source other than to supply the
requirements of the warning lamp 2(watts).
Such action will destroy the regulator warning lamp
circuit.
For test voltages refer to Generator output testing section.
See also additional information on regulator function earlier in
this instruction.
Page 2577 of 4264
ENGINE DRIVEABILITY AND EMISSIONS 6E–1
ENGINE
CONTENTS
C24SE ENGINE DRIVEABILITY AND EMISSIONS
ABBREVIATIONS CHARTS ......................... 6E-6
ECM Circuit Diagram (1/2) ............................ 6E-11
ECM Circuit Diagram (2/2) ............................ 6E-12
GROUND POINT CHART - LHD G.EXP (1/4) 6E-13
GROUND POINT CHART - RHD G.EXP (1/4) 6E-17
LOCATION ................................................... 6E-21
CABLE HARNESS & CONNECTOR
LOCATION .............................................. 6E-23
CABLE HARNESS & CONNECTOR
LOCATION LHD ................................... 6E-24
CABLE HARNESS & CONNECTOR
LOCATION RHD ................................... 6E-25
CONNECTOR LIST ...................................... 6E-28
RELAY AND FUSE ....................................... 6E-30
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-30
FUSE AND RELAY LOCATION (LHD & RHD) 6E-32
ECM WIRING DIAGRAM (1/9) ..................... 6E-33
ECM WIRING DIAGRAM (2/9) ..................... 6E-34
ECM WIRING DIAGRAM (3/9) ..................... 6E-35
ECM WIRING DIAGRAM (4/9) ..................... 6E-36
ECM WIRING DIAGRAM (5/9) ..................... 6E-37
ECM WIRING DIAGRAM (6/9) ..................... 6E-38
ECM WIRING DIAGRAM (7/9) ..................... 6E-39
ECM WIRING DIAGRAM (8/9) ..................... 6E-40
ECM WIRING DIAGRAM (9/9) ..................... 6E-41
ECM CONNECTOR PIN ASSIGNMENT &
OUTPUT SIGNAL .................................... 6E-42
GENERAL DESCRIPTION FOR ECM AND
SENSORS ............................................... 6E-48
Engine Control Module (ECM) ................... 6E-48
Manifold Absolute Pressure (MAP) Sensor 6E-48
Throttle Position Sensor (TPS) .................. 6E-49
Idle Air Control (IAC) Valve ....................... 6E-49
Crankshaft Position (CKP) Sensor ............ 6E-50
Knock Sensor (KS) .................................... 6E-50
Engine Coolant Temperature (ECT) Sensor 6E-50
Intake Air Temperature (IAT) Sensor ........ 6E-51
Vehicle Speed Sensor (VSS) .................... 6E-51
Heated Ox ygen (O
2) Sensor ..................... 6E-51
GENERAL DESCRIPTION FOR FUEL
METERING .............................................. 6E-52Battery Voltage Correction Mode ............... 6E-52
Clear Flood Mode ...................................... 6E-52
Deceleration Fuel Cutoff (DFCO) Mode .... 6E-52
Engine Speed/ Vehicle Speed/ Fuel Disable
Mode ........................................................ 6E-52
Acceleration Mode ..................................... 6E-52
Fuel Cutoff Mode ....................................... 6E-52
Starting Mode ............................................ 6E-52
Run Mode .................................................. 6E-52
Fuel Metering System Components .......... 6E-53
Fuel Injector ............................................... 6E-53
Fuel Pressure Regulator ............................ 6E-53
Fuel Rail ..................................................... 6E-53
Fuel Pump Electrical Circuit ....................... 6E-53
Thottle Body Unit ....................................... 6E-53
GENERAL DESCRIPTION FOR ELECTRIC
IGNITION SYSTEM ................................. 6E-54
Spark Plug ................................................. 6E-54
GENERAL DESCRIPTION FOR EVAPORATIVE
EMISSION SYSTEM ............................... 6E-57
EVAP Emission Control System Purpose .. 6E-57
EVAP Emission Control System Operation 6E-57
System Fault Detection .............................. 6E-57
POSITIVE CRANKCASE VENTILATION (PCV)
SYSTEM .................................................. 6E-59
Crankcase Ventilation System Purpose .... 6E-59
A/C CLUTCH DIAGNOSIS ........................ 6E-60
A/C Clutch Circuit Operation ...................... 6E-60
A/C Clutch Circuit Purpose ........................ 6E-60
A/C Request Signal ................................... 6E-60
ISUZU STRATEGY BASED DIAGNOSTICS 6E-61
Overview .................................................... 6E-61
STRATEGY BASED DIAGNOSTICS CHART 6E-61
Diagnostic Thought Process ...................... 6E-62
1. Verify the Complaint .............................. 6E-62
2. Perform Preliminary Checks .................. 6E-62
3. Check Bulletins and Troubleshooting Hints 6E-63
4. Perform Service Manual Diagnostic Checks 6E-63
5a and 5b. Perform Service Manual Diagnostic
Procedures .............................................. 6E-63
5c. Technician Self Diagnoses .................. 6E-63
5d. Intermittent Diagnosis .......................... 6E-64
Page 2578 of 4264
6E–2 ENGINE DRIVEABILITY AND EMISSIONS
5e. Vehicle Operates as Designed ............ 6E-65
6. Re-examine the complaint ..................... 6E-66
7. Repair and Verify Fix ............................. 6E-66
GENERAL SERVICE INFORMATION .......... 6E-67
On-Board Diagnostic (OBD) ...................... 6E-68
On-Board Diagnostic Tests ....................... 6E-68
The Diagnostic Executive .......................... 6E-68
Diagnostic Information ............................... 6E-68
Check Engine Lamp .................................. 6E-68
Data Link Connector (DLC) ....................... 6E-68
Tech 2 Operating Flow Cart (Start Up) ...... 6E-70
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ......................................... 6E-72
TYPICAL SCAN DATA & DEFINITIONS
(O2 SENSOR DATA) .................................. 6E-74
MISCELLANEOUS TEST ............................. 6E-76
PLOTTING SNAPSHOT GRAPH ................. 6E-78
Plotting Graph Flow Chart (Plotting graph after
obtaining vehicle information) .................. 6E-79
Flow Chart for Snapshot Replay
(Plotting Graph) ....................................... 6E-80
SNAPSHOT DISPLAY WITH TIS2000 ......... 6E-81
ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK
6E-98
Circuit Description ......................................... 6E-90
Diagnostic Aids ............................................. 6E-90
Test Description ............................................ 6E-90
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK .................................................... 6E-91
NO CHECK ENGINE LAMP (MIL) ................ 6E-94
Circuit Description ..................................... 6E-94
Diagnostic Aids .......................................... 6E-94
No Check Engine Lamp (MIL) ................... 6E-94
CHECK ENGINE LAMP (MIL) “ON” STEADY 6E-96
Circuit description ...................................... 6E-96
Diagnostic Aids .......................................... 6E-96
Check Engine Lamp (MIL) “ON” Steady .... 6E-96
FUEL METERING SYSTEM CHECK ........... 6E-98
FUEL INJECTOR COIL TEST PROCEDURE
AND FUEL INJECTOR BALANCE TEST
PROCEDURE ............................................. 6E-98
Test Description ......................................... 6E-98
Injector Coil Test Procedure (Steps 1-6)
and Injector Balance Test Procedure
(Steps 7-11) ............................................. 6E-99
Injector Coil Test Procedure (Steps 1-6)
and Injector Balance Test Procedure
(Steps 7-11) ............................................. 6E-100
FUEL SYSTEM ELECTRICAL TEST ........... 6E-103
Circuit Description ..................................... 6E-103
Diagnostic Aids .......................................... 6E-104Fuel Pressure Relief Procedure ................. 6E-104
Fuel Pressure Gauge Installation .............. 6E-104
Fuel System Electrical Test ....................... 6E-104
FUEL SYSTEM DIAGNOSIS ........................ 6E-108
Circuit Description ...................................... 6E-108
Test Description ......................................... 6E-108
Fuel Pressure Relief Procedure ................. 6E-109
Fuel Pressure Gauge Installation .............. 6E-109
Fuel System Diagnosis .............................. 6E-110
ECM DIAGNOSTIC TROUBLE CODES (DTC) 6E-113
DIAGNOSTIC TROUBLE CODE (DTC) P0107
MANIFOLD ABSOLUTE PRESSURE
CIRCUIT LOW INPUT ................................ 6E-119
Circuit Description ...................................... 6E-119
Diagnostic Aids .......................................... 6E-119
Diagnostic Trouble Code (DTC) P0107
Manifold Absolute Pressure Circuit Low
Input ......................................................... 6E-120
DIAGNOSTIC TROUBLE CODE (DTC) P0108
MANIFOLD ABSOLUTE PRESSURE
CIRCUIT HIGH INPUT ............................... 6E-123
Circuit Description ...................................... 6E-123
Diagnostic Aids .......................................... 6E-124
Diagnostic Trouble Code (DTC) P0108
Manifold Absolute Pressure Circuit High
Input ......................................................... 6E-124
DIAGNOSTIC TROUBLE CODE (DTC) P0112
INTAKE AIR TEMPERATURE SENSOR LOW
INPUT ......................................................... 6E-127
Circuit Description ...................................... 6E-127
Diagnostic Aids .......................................... 6E-127
Diagnostic Trouble Code (DTC) P0112
Intake Air Temperature Sensor Low Input 6E-128
DIAGNOSTIC TROUBLE CODE (DTC) P0113
INTAKE AIR TEMPERATURE SENSOR HIGH
INPUT ......................................................... 6E-131
Circuit Description ...................................... 6E-131
Diagnostic Aids .......................................... 6E-131
Diagnostic Trouble Code (DTC) P0113
Intake Air Temperature Sensor High Input 6E-132
DIAGNOSTIC TROUBLE CODE (DTC) P0117
ENGINE COOLANT TEMPERATURE
SENSOR LOW INPUT ................................ 6E-136
Circuit Description ...................................... 6E-136
Diagnostic Aids .......................................... 6E-136
Diagnostic Trouble Code (DTC) P0117
Engine Coolant Temperature Sensor Low
Input ......................................................... 6E-137
DIAGNOSTIC TROUBLE CODE (DTC) P0118
ENGINE COOLANT TEMPERATURE
SENSOR HIGH INPUT ............................... 6E-139
Circuit Description ...................................... 6E-139
Page 2581 of 4264
ENGINE DRIVEABILITY AND EMISSIONS 6E–5
ENGINE CRANKS BUT WILL NOT RUN ..... 6E-233
HARD START SYMPTOM ............................ 6E-236
ROUGH, UNSTABLE, OR INCORRECT IDLE,
STALLING SYMPTOM ............................... 6E-239
SURGES AND/OR CHUGS SYMPTOM ...... 6E-242
HESITATION, SAG, STUMBLE SYMPTOM 6E-245
CUTS OUT, MISSES SYMPTOM ................. 6E-248
LACK OF POWER, SLUGGISH OR SPONGY
SYMPTOM ................................................. 6E-251
DETONATION/SPARK KNOCK SYMPTOM 6E-254
POOR FUEL ECONOMY SYMPTOM .......... 6E-256
EXCESSIVE EXHAUST EMISSIONS OR
ODORS SYMPTOM ................................... 6E-258
DIESELING, RUN-ON SYMPTOM ............... 6E-261
BACKFIRE SYMPTOM ................................. 6E-262
ON-VEHICLE SERVICE PROCEDURE ....... 6E-264
ENGINE CONTROL MODULE (ECM) .......... 6E-264
CRANKSHAFT POSITION (CKP) SENSOR 6E-264
ENGINE COOLANT TEMPERATURE (ECT)
SENSOR .................................................... 6E-265
INTAKE AIR TEMPERATURE (IAT) SENSOR 6E-265
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSOR .................................................... 6E-266
THROTTLE POSITION SENSOR (TPS) ...... 6E-266
IDLE AIR CONTROL (IAC) VALVE .............. 6E-267
KNOCK SENSOR ......................................... 6E-268
POWER STEERING PRESSURE (PSP)
SWITCH ..................................................... 6E-268
HEATED OXYGEN SENSOR (HO2S) ......... 6E-269
EVAP CANISTER PURGE VALVE SOLENOID 6E-269
FUEL PRESSURE RELIEF .......................... 6E-270
FUEL RAIL ASSEMBLY ............................... 6E-270
FUEL INJECTOR .......................................... 6E-271
FUEL PRESSURE REGULATOR ................ 6E-273
IGNITION COIL ............................................ 6E-275
SPARK PLUGS ............................................ 6E-275
SPARK PLUG CABLES ................................ 6E-277
EMISSION CONTROL ; CO ADJUSTER (W/O
CATALYSTIC CONVERTER) .................. 6E-277
SPECIAL SERVICE TOOLS ......................... 6E-279
Page 2582 of 4264
6E–6 ENGINE DRIVEABILITY AND EMISSIONS
ABBREVIATIONS CHARTS
A bbreviations A ppellation
A/C Air Conditioner
A/T Automatic Transmission
ACC Accessory
BLK Black
BLU Blue
BRN Brown
CEL Check Engine Lamp
CKP Crankshaft Position
DLC Data Link Connector
DTC Diagnostic Trouble Code
DVM Digital Volt Meter
ECM Engine Control Module
ECT Engine Coolant Temperature
EEPROM Electrically Erasable & Programmable Read Only Memory
EVAP Evaporative Emission
EVRV Electric Vacuum Regulating Valve
EXH Exhaust
FT Fuel Temperature
GND Ground
GRY Gray
HOS2 Heated Ox ygen Sensor
IAC Idel Air Control
IAT Intake Air Temperature
IG Ignition
ITP Intake Throttle Position
KS Knock Sensor
M/T Manual Transmission
MAP Manifold Absolute Pressure
MIL Malfunction Indicator Lamp
OBD On-Board Diagnostic
ORN Orange
OT Oil Temperature
PNK Pink
RED Red
SW Switch
TB Throttle Body
TEMP Temperature
TP Throttle Posi tion
VCC Voltage Constant Control
VSS Vehicle Speed Sensor
WHT Whi te
Y EL Yellow
Page 2585 of 4264
ENGINE DRIVEABILITY AND EMISSIONS 6E–9
(1) Crankshaft Position (CKP) Sensor(1) Knock Sensor (KS)
(1)
(2)Engine Coolant Temperature (ECT) Sensor
Thermo Meter Sensor
21
(1) Manifold Absolute Pressure (MAP) Sensor
(1)
(2)Throttle Position Sensor
Idle Air Control (IAC) Valve
2
1
(1) EVAP Purge Solenoid
Page 2608 of 4264
6E–32 ENGINE DRIVEABILITY AND EMISSIONS
FUSE A ND RELAY LOCATION (LHD & RHD)
FUSE
SLOW BLOW FUSE
RELAYNo. Capacity Indication on label No. Capacity Indication on label
1——12 15A CIGER
2 10A ABS 13 15A AUDIO (+B)
3 10A TRAILER 14 20A DOOR LOCK
4 15A BACK UP 15 10A METER (+B)
5 15A METER 16 10A ROOM
6 10A TURN 17 10A ANTI THEFT
7 15A ELEC.IG 18 15A STOP
8 15A ENGINE 19 15A ACC SOCKET
9 20A FRT WIPER 20 10A STARTER
10 15A EGR 21 10A SRS
11 10A AUDIO
No. Capacity Indication on label
22 20A RR DEF
23 30A POWER WINDOW
Connector No. B-7 B-8 B-40
C24SE REAR DEFOGGER POWER WINDOW ACC SOCKET
FUSE BOX
Page 2624 of 4264
6E–48 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR ECM AND
SENSORS
Engine Control Module (ECM)
The engine control module (ECM) is located on the
intake manifold. The ECM controls the following.
Fuel metering system
Ignition timing
On-board diagnostics for electrical functions.
The ECM constantly observes the information from vari-
ous sensors. The ECM controls the systems that affect
vehicle performance. And it performs the diagnostic
function of the system.
The function can recognize operational problems, and
warn to the driver through the check engine lamp, and
store diagnostic trouble code (DTC). DTCs identify the
problem areas to aid the technician in marking repairs.
The input / output devices in the ECM include analog to
digital converts, signal buffers, counters and drivers.
The ECM controls most components with electronic
switches which complete a ground circuit when turned
on.
Inputs (Operating condition read):
Battery voltage
Electrical ignition
Ex haust oxygen content
Intake manifold pressure
Intake air temperature
Engine coolant temperature
Crankshaft positionKnock signal
Throttle position
Vehicle speed
Power steering pressure
Air conditioning request on or off
Outputs (Systems controlled):
Ignition control
Fuel control
Idle air control
Fuel pump
EVAP canister purge
Air conditioning
Diagnostics functions
Manifold Absolute Pressure (MAP) Sensor
The MAP sensor is a strain gage. A pressure strains the
resistance on the silicon base. At that time the
resistance value changes. And it changes voltage. In
other words it measures a pressure value. It is installed
to the intake manifold. Output voltage of the MAP
sensor is low as pressure is low. (1) J1 Port
(2) J2 Port
12
C h arac teris tic of MA P S ens or -R ef erenc e-
0 0.51 1.52 2.53 3.54 4.55
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
Mani fold A bs olute P res s ure (K P a) (T ec h2 Reading)
Output Voltage (V)
Page 2628 of 4264
6E–52 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR FUEL
METERING
The fuel metering system starts with the fuel in the fuel
tank. An electric fuel pump, located in the fuel tank,
pumps fuel to the fuel rail through an in-line fuel filter.
The pump is designed to provide fuel at a pressure
above the pressure needed by the injectors.
A fuel pressure regulator in the fuel rail keeps fuel
available to the fuel injectors at a constant pressure.
A return line delivers unused fuel back to the fuel tank.
The basic function of the air/fuel metering system is to
control the air/fuel delivery to the engine. Fuel is
delivered to the engine by individual fuel injectors
mounted in the intake manifold.
The main control sensor is the heated ox ygen sensor
located in the ex haust system. The heated ox ygen
sensor reports to the ECM how much oxygen is in the
ex haust gas. The ECM changes the air/fuel ratio to the
engine by controlling the amount of time that fuel
injector is “On”.
The best mix ture to minimize exhaust emissions is 14.7
parts of air to 1 part of gasoline by weight, which allows
the catalytic converter to operate most efficiently.
Because of the constant measuring and adjusting of the
air/fuel ratio, the fuel injection system is called a “closed
loop” system.
The ECM monitors signals from several sensors in
order to determine the fuel needs of the engine. Fuel is
delivered under one of several conditions called “mode”.
All modes are controlled by the ECM.
Battery Voltage Correction Mode
When battery voltage is low, the ECM will compensate
for the weak spark by increasing the following:
The amount of fuel delivered.
The idle RPM.
Clear Flood Mode
Clear a flooded engine by pushing the accelerator pedal
down all the way. The ECM then de-energizes the fuel
injectors. The ECM holds the fuel injectors de-energized
as long as the throttle remains above 75% and the
engine speed is below 800 RPM. If the throttle position
becomes less than 75%, the ECM again begins to pulse
the injectors ON and OFF, allowing fuel into the
cylinders.
Deceleration Fuel Cutoff (DFCO) Mode
The ECM reduces the amount of fuel injected when it
detects a decrease in the throttle position and the air
flow. When deceleration is very fast, the ECM may cut
off fuel completely. Until enable conditions meet the
engine revolution less 1000 rpm or manifold absolute
pressure less than 10 kPa.
Engine Speed/ Vehicle Speed/ Fuel Disable
Mode
The ECM monitors engine speed. It turns off the fuel
injectors when the engine speed increases above 6000
RPM. The fuel injectors are turned back on when
engine speed decreases below 3500 RPM.
Acceleration Mode
The ECM provides ex tra fuel when it detects a rapid
increase in the throttle position and the air flow.
Fuel Cutoff Mode
No fuel is delivered by the fuel injectors when the
ignition is OFF. This prevents engine run-on. In addition,
the ECM suspends fuel delivery if no reference pulses
are detected (engine not running) to prevent engine
flooding.
Starting Mode
When the ignition is first turned ON, the ECM energizes
the fuel pump relay for two seconds to allow the fuel
pump to build up pressure. The ECM then checks the
engine coolant temperature (ECT) sensor and the
throttle position sensor to determine the proper air/fuel
ratio for starting.
The ECM controls the amount of fuel delivered in the
starting mode by adjusting how long the fuel injectors
are energized by pulsing the injectors for very short
times.
Run Mode
The run mode has the following two conditions:
Open loop
Closed loop
When the engine is first started, the system is in “open
loop” operation. In “Open Loop,” the ECM ignores the
signal from the heated oxygen sensor (HO2S). It
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAP sensors.
The system remains in “Open Loop” until the following
conditions are met:
The HO2S has a varying voltage output showing that
it is hot enough to operate properly (this depends on
temperature).
The ECT has reached a specified temperature.
A specific amount of time has elapsed since starting
the engine.
Engine speed has been greater than a specified RPM
since start-up.
The specific values for the above conditions vary with
different engines and are stored in the programmable
read only memory (PROM). When these conditions are
met, the system enters “closed loop” operation. In
“closed loop,” the ECM calculates the air/fuel ratio
(injector on-time) based on the signal from the HO2S.
This allows the air/fuel ratio to stay very close to 14.7:1.
Page 2648 of 4264
6E–72 ENGINE DRIVEABILITY AND EMISSIONS
TYPICAL SCAN DATA & DEFINITIONS (ENGINE DATA)
Use the Typical Values Table only after the On-Board Diagnostic System Check has been completed, no DTC(s) were
noted, and you have determined that the on-board diagnostics are functioning properly. Tech 2 values from a
properly-running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approx imately
80 deg.)
Tech 2 ParameterUnitsIdle2000rpmDescription
1 Engine Speed rpm775 - 8751950 - 2050 The actual engine speed is measured by ECM from the
CKP sensor 58X signal.
2 Desired Idle Speed rpm825800 - 850 The desired engine idle speed that the ECM
commanding. The ECM compensates for various engine
loa ds.
3 Engine Coolant
Te mpe rature°C or °F80 - 9080 - 90 The ECT is measured by ECM from ECT sensor output
voltage. When the engine is normally warm upped, this
data displays approximately 80 °C or more.
4 Sta rt Up ECT (Engine
Coolant Temperature)°C or °FDepends on ECT
a t start-upDepends on ECT
at sta rt-upStart-up ECT is measured by ECM from ECT sensor
output voltage when engine is started.
5Inta ke Air
Temperature °C or °FDe pe nds on
ambient tempDepends on
ambient tempThe IAT is mea sure d by ECM from IAT sensor o utput
voltage. This data is changing by intake air temperature.
6 Sta rt Up IAT (Inta ke
Air Temperature)°C or °FDepends on IAT at
sta rt-upDepends on IAT at
start-upStart-up IAT is me asured by ECM fro m IAT se nso r o utput
voltage when engine is started.
7 Manifold Absolute
Pre ssurekPa31 - 3625 - 30The MAP (kPa ) is me asure d by ECM fro m MAP o utput
voltage. This data is changing by inlet manifold pressure.
8 Barometric Pressure kPaDe pe nds on
altitudeDepends on
altitudeThe ba rome tric pre ssure is me asured by ECM fro m the
MAP sensor output voltage monitored during key up and
w ide o pe n thro ttle. This data is cha nging by a ltitude.
9 Throttle Position %02-4 Throttle position operating angle is measured by the
ECM from throttle position output voltage. This should
displa y 0% at idle a nd 99 - 100% at full throttle .
10 Calculated Air Flow g/s3.5 -4.508.0 - 10.0 This displays calculated air mount from MAP sensor
output. This data is changing by inlet manifold pressure .
11 Air Fuel Ratio14.6:114.6:1 This displays the ECM commanded value. In closed loop,
this should normally be displayed around 14.2:1 - 14.7:1.
12 Spark Advance °CA8 - 1525 - 32 This displays the amount of spark advance being
commanded by the ECM.
13 Engine Load %2 - 55 - 10 This displays is calculated by the ECM form engine
speed and MAF sensor reading. Engine load should
incre ase with an incre ase in engine spe ed or air flo w
amount.
14 Injection Pulse Width ms1.0 - 3.0 3.0 - 4.0 This displays the amount of time the ECM is
commanding each injector On during each engine cycle.
A lo nger injecto r pulse width will ca use more fuel to be
delivered. Injector pulse width should increase with
increased engine load.
15 Fuel System Status Open Loop/
Close LoopClo se Loo pClose Loop When the engine is first started the system is in “Open
Loop” operation. In “Open Loop”, the ECM ignores the
signal from the oxygen sensors. When various conditions
(ECT, time from start, engine speed & oxygen sensor
o utput) are me t, the syste m e nte rs “Closed Lo op”
o pera tio n. In “Close d Lo o p”, the ECM ca lculate s the air
fuel ratio based on the signal from the oxygen sensors.
16 Knock Present Yes/NoNoNo This displays knock sensor detection status. When
engine knock is occurred, displays "Yes".
17 Knock Counter-- This displays the number of knock during a ignition cycle.
18 Kno ck Reta rd °CA00 This displa ys the commande d ignitio n spa rk timing re tard
timing based on the signal from the knock sensor.
19 A/C Clutch Re la y On/OffOffOff This display s whe the r the ECM has co mma nde d the A/C
co mpre ssor clutch “On” or “Off”.