ignition ISUZU TROOPER 1995 Workshop Manual

6E2-8 DRIVEABILITY AND EMISSIONS
Former ISUZU Name New ISUZU Name Term
Crankshaft Reference Signal Crankshaft Position -CKP
Crankshaft Sensor
Crankshaft Position Sensor -CKP Sensor
Crankshaft Speed
Engine Speed -
RPM
Crankshaft Speed Sensor
Engine Speed Sensor -RPM Sensor
CTS Engine Coolant Temperature Sensor -ECT Sensor
D.I.S Electronic Ignition -El
Detonation Sensor
Knock Sensor-KS
Diagnostic Circuit Check On-Board Diagnostic System Check -OBD System Check
Diagnostic Code Diagnostic Trouble Code -DTC
Diagnostic Mode
Diagnostic Test Mode-DTM
Diagnostic Terminal
Diagnostic Test Terminal -DTT
Digital Electronic
Fuel Injection Multipart Fuel Injection -MFI
Digital Fuel Injection Multipart Fuel Injection -MFI
Digital Fuel Injection Sequential Multipart Fuel Injection -SFI
Direct Ignition Systme Electronic Ignition System -El System
DIS Electronic Ignition -El
DIS Module
Ignition Control Module -ICM
DIS Reference Electronic Ignition Reference -El Reference
Distributor
HEI Module Distributor Ignition Control Module -Dl Control Module
Distributorless Ignition System Electronic Ignition System -
El System
ECM Engine Control Module -ECM
ECM Controlled Air Conditioning Air Conditioning Compressor Clutch Control System -A/C
Compressor Clutch Control System
ECU Transmission Control Module -TCM
EECS Evaporative Emission-EVAP
EEPROM Electrically Erasable Programmable Read Only Memory-
EEPROM
EFI Throttle Body Fuel Injection -TBI
EGR Exhaust Gas Recirculation -EGR
EGR B/P Transducer EGR Backpressure Transducer -EGR BPT
EGR Valve Exhaust Gas Recirculation Valve -EGR Valve
Electronic Control Module Engine Control Module -ECM
Electronic Control Unit Powertrain Control Module -PCM
Electronic Engine Control Module Engine Control Module -ECM
Electronic Fuel Injection Multipart Fuel Injection -MFI
Electronic Spark Control Circuit Knock Sensor Circuit -KS Circuit
Electronic Spark Control System Knock Sensor System -KS System
Electronic Spark Timing Ignition
Control -IC
Electronic Spark Timing Circuit Ignition Control Circuit -IC Circuit
Electronically Controlled Pulse
Air Pulsed Secondary Air Injection System -PAIR System
System
Engine
Calibration Unit Programmable Read Only Memory -PROM
•

DRIVEABILITY AND EMISSIONS 6E2-9
Former ISUZU Name New ISUZU Name Term
Engine Coolant Temperature
Engine Coolant Temperature -ECT
Engine Crank Signal Crankshaft Position -CKP
Engine RPM Engine Speed -RPM
ESC Knock Sensor System-KS System
ESC Module Knock Sensor Module -KS Module
EST Ignition Control -IC
Evaporative Emission Control Evaporative Emission Control System -EVAP Control System
Exhaust Oxygen Sensor
Oxygen Sensor -
02S
Fourth Gear
Fourth Gear -4GR
Fuel Pump Fuel Pump -FP
Fuel Pump Relay
Fuel Pump Relay -FP Relay
GND Ground-GND
GAD Ground-GND
Ground Ground-GND
HC Hydrocarbon -HC
Hg Hydrargyrum-Hg
High Energy Ignition Distributor Ignition -Dl
Hydrocarbons
Hydrocarbon -HC
lAC
Idle Air Control-lAC
lAC Valve
Idle
Air Control Valve-lAC Valve
IACV Idle
Air Control Valve -lAC Valve
Idle
Air Control Idle Air Control -lAC
Idle
Speed Control Idle Speed Control -ISC
Ignition Module
Ignition Control Module -ICM
Inter Cooler Charge Air Cooler -CAC
ISC Idle Speed Control -ISC
Knock Signal Knock Sensor Signal -KC Signal
Lean Exhaust
Lean Heated Oxygen Sensor Signal -Lean H02S Signal
Lean Exhaust
Lean Oxygen Sensor Signal -Lean 02S Signal
Lean Mixture Signal Lean Heated Oxygen Sensor Signal -Lean H02S Signal
Lean Mixture Signal Lean Oxygen Sensor Signal -Lean 02S Signal
M/C Mixture Control -MC
Manifold Air Temperature Intake Air Temperature-IAT
Manifold
Air Temperature Sensor Intake Air Temperature Sensor-IAT Sensor
Manifold Pressure Manifold Absolute Pressure -MAP
MAP
Manifold Absolute Pressure -MAP
MAP Sensor
Manifold Absolute Pressure Sensor -MAP Sensor
MAT Intake Air Temperature-IAT
MEM-CAL Programmable Read Only Memory -PROM
Mem-Cal Error Programmable Read Only Error -PROM Error
Mode Diagnostic
Test Mode -DTM

DRIVEABILITY AND EMISSIONS 6E2-11
Former ISUZU Name New ISUZU Name Term
Throttle Position Switch Wide Open Throttle Switch -WOT Switch
Throttle Switch
Wide Open Throttle Switch -WOT Switch
Throttle Valve Throttle
Body -TB
TPS Throttle Position Sensor -TP Sensor
Transmission ECU Transmission Control Module -TCM
TWC Three
Way
Catalytic Converter -TWC
Vacuum Switching Valve Vacuum Switch Valve -VSV
Vehicle Speed Sensor Vehicle
Speed Sensor
-VSS
vss Vehicle Speed Sensor -VSS
vsv Vacuum Switch Valve -VSV
WOT
Wide Open Throttle -WOT
ABBREVIATIONS AND GLOSSARY OF TERMS
Abbreviations used in this section are listed below in
alphabetical order with an explanation of the
abbreviation. There are some variations in the use
of
periods and in capitalization (as mph, m.p.h., Mph, and
MPH) for abbreviations used in this Section, but all
types are acceptable.
A/T -AUTOMATIC TRANSMISSION
AVM-ANALOG VOLT METER
CKT -CIRCUIT
DOHC-DUAL OVERHEAD CAMSHAFTS
DTM-DIAGNOSTIC TEST MODE
A particular state of operation.
DVOM-DIGITAL VOLT OHM METER
ECT -ENGINE COOLANT TEMPERATURE
ECM-ENGINE CONTROL MODULE
A metal box (located in passenger compartment)
containing
electronic circuitry which electrically
controls
and monitors air/fuel and emission systems
on
computer command control, and turns "ON" the
"Check Engine"
Malfunction Indicator Lamp when a
malfunction occurs in the system.
EGR-EXHAUST GAS RECIRCULATION
Method of reducing NOx emission levels by causing
exhaust gas
to be added to air/fuel mixture in
combustion chamber, thus
cooling combustion.
FED-FEDERAL
Vehicle/Engine available in all states except California.
GROUND
The negative (-) side of the battery. Also could be a
wire (conductor) shorted to ground.
HC-HVDROCARBONS
One of the pollutants found in engine exhaust.
Hg-MERCURV
A calibration material used as a standard for vacuum
measurement.
HIGH IMPEDANCE VOLTMETER
Has high opposition to the flow of electrical current.
Good
for reading circuits with low currentflow, such as
found in electronic systems because it allows tests to
be made without affecting the circuit.
IAT -INTAKE AIR TEMPERATURE
Air temperature in the intake manifold.
IAT-INTAKE AIR TEMPERATURE SENSOR
Measures the underhood temperature.
IC-IGNITION CONTROL
ECM controlled spark timing
IDEAL MIXTURE
The air/fuel ratio which provides the best
performance,
while maintaining maximum conversion
of exhaust emissions. Typically it is 14.7:1.
IGN-IGNITION
INPUTS
Information from sources (such as Engine Coolant
Temperature Sensors, Oxygen Sensor, etc.) to the
ECM that indicate how the systems are performing.
INTERMITTENT
Occurs now and then; not continuously. In electrical
circuits, refers to occasional open, short, or ground.
liP-INSTRUMENT PANEL
ISC-IDLE SPEED CONTROL
ECM-controlled solenoid used to route vacuum to
control idle speed under various engine loads.
KM/H-KILOMETER PER HOUR
A metric unit measuring speed needed to travel
distance of one kilometer (1 000 meters) in one hour.

SECTION II A"
DIAGNOSTIC PROCEDURE SUMMARY
•IGNITION "ON", ENGINE STOPPED. •IS THE MALFUNCTION INDICATOR LAMP "ON"?
•
JUMPER DATA LINK CONNECTOR TERM. 1 TO 3. • DOES MALFUNCTION INDICATOR LAMP FLASH DIAGNOSTIC TROUBLE CODE (DTC) 12?
REFER TO APPLICABLE DTC CHART, START WITH LOWEST DTC.
"SCAN TOOL" SERIAL DATA. REPAIR AS NECESSARY. IF ALL OK, SEE DRIVEABILITY SYMPTOMS IN SECTION B.
Fig. 6E2-2
r
DRIVEABILITY AND EMISSIONS 6E2-13
This is the starting point for the diagnostic procedures.
The diagnostic charts are
related to the Engine Control
Module
(ECM) and will determine if the ECM is working
properly.
This section diagnoses the fuel system controlled by
the
ECM and has charts to diagnosis a circuit when the
ECM has displayed a trouble code.
The
way to approach a problem is to follow some basic
steps.
1.
Are the On-Vehicle Diagnostics working?
We find this out by performing the "On-Board
Diagnostic System Check" Since this is the
starting point
for the diagnostic procedure,
always
begin here.
If the On-Vehicle Diagnostics aren't working, the "On­
Board Diagnostic System Check" will lead you to a
chart in Section
"A" to correct the problem. If the On­
Vehicle
Diagnostics are OK, the next step is:
2.
Is there a Trouble Code stored?
If a trouble code is stored, go directly to the
numbered
DTC chart in Section "A". This will
determine if the fault is still present. If no trouble
code is stored, the third step is:
3. "Scan Tool" Serial Data.
This
involves reading the various pieces of
information available on the Serial Data Stream
with one of the tools available for that purpose.
Information on these tools and the meaning of the
various
displays can be found in the following
paragraphs. Expected readings can be found on
the facing page
for the On-Board Diagnostic
System Check.
This procedure, which takes
only a short time, will help
lead
you to repair the problem in the least amount of
time.

THROTTLE ANGLE
Displays in percent the amount the throttle is
open.
HEATED OXYGEN SENSOR (H02S)
The reading will be read out in millivolts (mv) with
a range from 1 to 999 mv. If the reading is
consistently
below 350 (350 mv), the fuel system
is running
lean as seen by the Engine Control
Module
(ECM) and if the reading is consistently
above
550 (550 mv), the system is running rich.
VEHICLE SPEED SENSOR (VSS)
Displays vehicle speed, useful in checking
speedometer accuracy.
PROGRAMMABLE READ ONLY MEMORY
(PROM)
ID
In this position the last4 digits of the Mem-Cal part
number will be displayed.
REVOLUTION PER MINUTE (RPM)
Displays engine speed. Often useful if extra
reference pulses are suspected. A sudden high
revolution per minute indication while at a steady
throttle
would indicate electrical interference
(EMI) in the reference circuit. This interference is
usually caused by ECM wires too close to ignition
secondary wires
or an open electronic ignition
ground circuit.
MILE PER HOUR (MPH)
Displays vehicle speed. Useful in checking
speedometer accuracy.
ENGINE COOLANT TEMPERATURE (ECT)
Displays engine temperature in degress centi­
grade.
After engine is started the temperature
should rise steadily to about
85-95·c, then
stabilize
when the thermostat opens.
INTAKE AIR TEMPERATURE (IAT)
SENSOR
Displays temperature of the intake manifold air.
Should read close to ambient air temperature
when the engine is cold, and rise
as underhood
and engine temperature increases.
DRIVEABILITY AND EMISSIONS 6E2-15
MANIFOLD ABSOLUTE PRESSURE (MAP)
The Manifold Absolute Pressure (MAP) Sensor
produces a low signal voltage when MAP is low
(high vacuum) and a high voltage when the
pressure is high (low vacuum).
With the ignition on and the engine stopped, the
manifold absolute pressure is equal
to
atmospheric pressure and the signal voltage will
be high. This information is used by the ECM as an
indication of vehicle altitude and is referred to as
barometric pressure. Comparison of this
barometric pressure reading
with a known good
vehicle
with the same sensor is a good way to
check accuracy
of a "suspect" sensor. Readings
should be the same
±0.4 Volt.
MAP
Sensors have a colored plastic insert visible
in the connector cavity.
Sensors with the same
insert color are identical in calibration. The
harness electrical connector color should also be
the same
as the sensor insert color.
BAROMETRIC PRESSURE (BARO)
Displays the MAP reading before the engine was
started. This value
will vary depending on
Barometric Pressure and altitude.
EXHAUST GAS RECIRCULATION (EGR)
(ON/OFF)
The exhaust gas recirculation system uses a valve
controlled by vacuum to feed a small amount of
exhaust gas back into the intake manifold to
control formation
of NOx. Like all ECM outputs the
"Scan tool" only indicates that the ECM has
commanded the function and does
not indicate
that the function has
really happened.
SHORT TERM (S.T.) FUEL TRIM AND LONG
TERM (L.T.) FUEL TRIM
On Fuel Injected Engines, normal readings for
these positions are around 128. If higher, it
indicates that the ECM is adding fuel to the base
fuel calculation because the system is lean.
If the
numbers are below 128, the
ECM is taking out fuel
from the base calculation because the system is
rich. The
S.T. Fuel Trim is short term corrective
action while the
L.T. Fuel Trim portion (which is a
long term correction)
will only change if the
intergrator has seen a condition which lasts
for a
calibrated period
of time.

6E2-16 DRIVEABILITV AND EMISSIONS
LONG TERM (LT.) FUEL TRIM
There are from zero to seventeen different cells
which the Engine Control Module (ECM) learns at
depending on revolution per minute (rpm) and
manifold absolute pressure. This parameter
will
display what cell the ECM is using for the fuel
calculation at the time.
IDLE AIR CONTROL (lAC) COUNTS
This system is used to control engine idle speed to
the desired rpm, for different operating
conditions.
In this diagnostic test mode, the
numbers
will indicate what position the ECM
thinks the valve is in. The ECM moves the idle air
control in counts and these counts are displayed
on a
"Scan tool".
DESIRED REVOLUTION PER MINUTE
Indicates the rpm to which the ECM is trying to
control the idle.
AIR CONDITIONING (A/C) REQUEST
Displays the state of the Air Conditioning (A/C)
signal line to the ECM. Should read "YES"
whenever the A/C is requested.
AIR CONDITIONING {A/C) CLUTCH
Displays "ON" when the ECM has commanded
the
A/C Clutch "ON".
POWER STEERING PRESSURE (PSP)
SWITCH
Displays the state of switch. This reading may
vary
with the tool used and the type of switch
installed on the vehicle. The important thing is
that the reading changes state (switches) when
the steering is moved against the stops.
BA TTERV POSITIVE VOLTAGE
Displays the battery positive voltage detected at
the
ECM ignition input.
SPARK ADVANCE
This is a amount of total spark advance including
the base electronic ignition timing.
START UP ENGINE COOLANT
This parameter is the engine coolant temperature
at the
time the engine was started.
ENGINE SPEED (RPM)
RPM calculated during a crank mode, helpful in
diagnosing a NON-start condition.
FUEL TRIM ENABLE
This value is an indication when the Fuel Trim
Enable values are being updated within the ECM
program.
AIR/FUEL RATIO
This is the air to fuel ratio that is being
commanded to the injectors.
INDUCTION AIR CONTROL
The "Scan tool" will display the command being
given to the induction air control
plate system
solenoid.
SECTION B-DRIVEABILITY SYMPTOMS
Always start with Section "A" "On-Board Diagnostic
System Check" before proceeding to the driveability
symptoms.
Section "A" checks the ECM which may
cause the driveability problem. A definition
of each
symptom is included. This will then lead to the most
probable causes of the driveability problem.
SECTION C-COMPONENTS SYSTEMS
There are many component systems that are used to
control fuel and emissions. Section "C" introduces
each component system or control
with a general
description, diagnosis, and on-vehicle service.
Each
of the Section "C" diagnosis sections will contain
information on
how the "Scan tool" can be used for
diagnosing a particular component when a trouble
code has
not been set. (example: Section "C1" under
diagnosis
will explain how the "Scan tool" can be used
for diagnosis as well as what the normal readings
would be for the ECM Sensors.
•

DRIVEABILITY AND EMISSIONS 6E2-17
I OPERATING CONDITIONS READ I
I SYSTEMS CONTROLLED I
• Air Conditioning "On" or "Off" • Evaporative Emission Canister
• Engine Coolant Temperature Purge
• Crankshaft Position • Exhaust Gas Recirculation
• Exhaust Heated Oxygen Sensor • Ignition Control
• Electronic Ignition Reference • Fuel Control
• Crankshaft Position
ENGINE • Idle Air Control
• Engine Speed (RPM} CONTROL • Electric Fuel Pump
• Manifold Absolute Pressure (MAP)
MODULE • Air Conditioning
• Battery Positive Voltage (ECM) • Diagnostics
• Throttle Position Sensor • Malfunction Indicator Lamp
• Vehicle Speed Sensor • Diagnostic Test Terminal
• Fuel Pump Voltage • Data Output
• Power Steering Pressure • Transmission Control Module
• Intake Air Temperature • Knock Sensor (DOHC)
• Differential Pressure • Induction Air Control Plate System
• Knock Sensor (DOHC)
(DOHC)
• Exhaust Gas Recirculation Vacuum
• Air Conditioning High Side Pressure
Fig. 6E2-3
ENGINE CONTROL MODULE (ECM) AND
SENSORS
This Section describes the Engine Control Module
(ECM) and the information sensors in the system.
Figure (Fig. 6E2-3) shows the operating conditions
which the
ECM may read and the systems thatthe ECM
may control.
FUEL CONTROL SYSTEM
The ECM controls the air/fuel delivery to the combus­
tion chamber by
controlling the fuel flow through the
injector(s).
ELECTRIC FUEL PUMP (IN-TANK)
The in-tank fuel pump is controlled by the ECM. When
ignition is turned on, the
pump will run for 2 seconds,
then stop
unless the engine is cranking or running.
EVAPORATIVE EMISSION (EVAP) CONTROL
SYSTEM
This system has a canister which stores fuel vapor
from the fuel tank. The fuel vapor is removed from the
canister and consumed in the
normal combustion
process when the engine
is running.
IGNITION CONTROL (IC)
This system is controlled by the ECM which controls
spark advance (timing) and is used on all engines.
EXHAUST GAS RECIRCULATION (EGR)
The exhaust gas recirculation system uses ECM
controlled valve to feed a small amount of exhaust gas
back into the intake
manifold to control formation of
NOx.
AIR CONDITIONING (A/C) CLUTCH CONTROL
The ECM may control the air conditioning clutch on the
compressor
to improve idle quality.
POSITIVE CRANKCASE VENTILATION (PCV)
The PCV system passes crankcase vapors into the
intake
manifold. This system is not controlled by the
ECM and is used on all engines.

Tachometer
Use inductive trigger signal pickup type to check
revolution per minute.
Fig. 6E2-7
Multiport fuel injection (MFI) diagnostic kit
Used to diagnose MFI systems.
The kit
includes:
• Fuel
Pressure Gage-to check fuel pump pressure
and compare injector pressure
drop for equal fuel
distribution.
• Injector Test Light-to check electrical circuit to an
injector.
• Injector Test-to energize each fuel injector for a
precise
amount of time to perform injector
balance test in CHART C-2A by checking each
injector's pressure
drop using pressure gage.
MFI test kit: J-34730-8
Fuel pressure gage
Used to check and monitor fuel line pressure of port
fuel system.
MFI test kit: J-34730-8
Injector test light
Used to check electrical circuit to a port fuel injector.
MFI test kit: J-34730-8
Injector tester
Used to energize each fuel injector for a precise
amount of time to perform injector balance test in
CHART C-2A by checking each injector's pressure drop
using pressure gage.
MFI test kit: J-34730-8
DRIVEABILITY AND EMISSIONS 6E2-19
Fig. 6E2-8
Spark tester
Use to check available secondary ignition voltage.
Also called
an ST125.
Spark
tester: J-26792
Fig. 6E2-9
Connector test adapter kit
Used to make electrical test connections in current
Weather Pack, Metri-Pack and Micro-Pack
style
terminals.
Terminal test adapter kit: J-35616
Fig. 6E2-10

6E2-22 DRIVEABILITV AND EMISSIONS
(DOHC)
(SOHC)
VACUUM HOSE ROUNTING DIAGRAM
EGR
INDUCTION-----­
AIR CONTROL
VALVE
BACK PRESSURE
TRANSDUCER
t
TO
THROTTLE
BODY
FUELPRESSURE ~
CONTROL ~ MAPSENSOR
VALVE (..._ _____ R_A_D _I A_T_O_R ____ ___.)
MAP
SENSOR
EGR------,
BACK PRESSURE
TRANSDUCER
FUEL
TANK
VACUUM
SWITCH
VALVE
CHECK&
RELIEF
c:::=::::::::::::::;:T=====!.J VALVE
L-~~~~~ ...J;::...u..-+----'~THROTTLE BODY
IGNITION
CONTROL
MODULE <==><==::>
[ RADIATOR )
~---------------------
VACUUM
SWITCH
VALVE
FUEL PRESSURE
CONTROL
VALVE
..

DRIVEABILITY AND EMISSIONS 6E2-23
SECTION A
ENGINE COMPONENTS/WIRING DIAGRAMS/DIAGNOSTIC
CHARTS
CONTENTS
On-Board Diagnostic (OBD} System Check . 6E2-23
Basic Procedure . . . . . . . . . . . . . . . . . . . . . 6E2-23
Engine Component Location . . . . . . . . . . 6E2-24
Engine Control Module Wiring
Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . 6E2-26
Engine Control Module (ECM) Connector
Identification . . . . . . . . . . . . . . . . . . . . . 6E2-33
"SCAN TOOL" On-Board Diagnostic (OBD)
System Check . . . . . . . . . . . . . . . . . . . . 6E2-34
On-Board Diagnostic (OBD} System Check . 6E2-36
Won't Flash Diagnostic Trouble Code
(DTC)
12 No "Check Engine" Malfunction
Indicator Lamp (MIL)-Chart A-1 . . . . . . 6E2-38
No Data Link Connector (DLC) Data or
Won't Flash Diagnostic Trouble Code
(DTC)
21 "Check Engine" Malfunction
Indicator Lamp (MIL} "On" Steady-
Chart A-2 . . . . . . . . . . . . . . . . . . . . . . . . . 6E2-40
Engine Crank But Will Not
Run-Chart A-3 . . . . . . . . . . . . . . . . . . . . . 6E2:.....42
Fuel Pump Relay Circuit-Chart A-5 . . . . . 6E2-48
Fuel System Pressure Test-Chart A-7 ..• /6E2-50
Intake Manifold Diagnostic Plate Chart/
A-8 ......................... ,-:· . . . 6E2-56
Diagnostic Trouble Code (DTC~13 /
Heated Oxygen Sensor (H02 Circuit
(Open Grounded Circuit) . . . . . . . . . . . 6E2-58
Diagnostic Trouble Code (D'JiC) 14A
Engine Coolant Temperaiure (ECT}
Sensor Circuit (High -:remperature
Indicated) ....... /. . . . . . . . . . . . . . . . 6E2-60
Diagnostic Trouble P'ode (DTC} 14B
Engine
Coolan·vremperature (ECT)
Sensor Circuit'(Low Temperature
Indicated) ./. . . . . . . . . . . . . . . . . . . . . . . 6E2-62
Diagnostic Jtouble Code (DTC) 21A
Throtti~,.Position (TP) Sensor
Circu)t (Signal Voltage High) . . . . . . . . 6E2-64
Diag.,Ostic Trouble Code (DTC) 21B
Jflrottle Position (TP} Sensor
//Circuit (Signal Voltage Low} ........ 6E2-66
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK
The "On-Board Diagnostic System Check" verifies the
system is functioning correctly.
Some special
considerations
to keep in mind while making the "On­
Board Diagnostic System Check" are:
Diagnostic Trouble Code (DTC(23A
Intake Air Temperature (IAT)
Sensor Circuit (low Temperature
Indicated) ......................... 6E2-68
Diagnostic Trouble Code (DTC) 23B
Intake Air Temperature (IAT)
Sensor Circuit (High Temperature
Indicated) ... / ...................... 6E2-70
Diagnostic T[ouble Code (DTC} 24
Vehicle )!Peed Sensor (VSS} Circuit ... 6E2-72
DiagnostiC Trouble Code (DTC) 32
Exh,tist Gas Recirculation (EGR}
Cir,.Cuit ............................ 6E2-74
Dia,gnostic Trouble Code (DTC} 33A
·Manifold Absolute Pressure (MAP)
Sensor Circuit (Signal Voltage
High-Low Vacuum) ................. 6E2-76
Diagnostic Trouble Code (DTC) 33B
Manifold Absolute Pressure (MAP}
Sensor Circuit (Signal Voltage
Low-High Vacuum) ................. 6E2-78
Diagnostic Trouble Code (DTC) 42
Ignition Control (IC) Circuit . . . . . . . . . . 6E2-80
Diagnostic Trouble Code (DTC} 43
Knock Sensor (KS} Circuit (DOHC) .... 6E2-82
Diagnostic Trouble Code (DTC) 44
Heated Oxygen Sensor (H02S} Circuit
(Lean Heated Oxygen Sensor (H02S)
Signal Indicated} . . . . . . . . . . . . . . . . . . . 6E2-84
Diagnostic Trouble Code (DTC) 45
Heated Oxygen Sensor (H02S) Circuit
(Rich Heated Oxygen Sensor (H02S)
Signal Indicated) . . . . . . . . . . . . . . . . . . . 6E2-86
Diagnostic Trouble Code (DTC) 51
Engine Control Module (ECM} Failure
ECM Failed
or Electrically Erasable
Programmable Read Memory Only
Failure} ........................... 6E2-88
Blocking Drive Wheels
The vehicle drive wheels should always be
blocked
while checking the system.
BASIC PROCEDURE
If the basic information on using the diagnostic
procedures contained in this section has
not been
reviewed, refer
to the introduction of this section.