sensor ISUZU AXIOM 2002 Service Repair Manual

6E±93
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Reduced Power Lamp (RPL) ªONº Steady
060R200073
Circuit Description
The Reduced Power lamp (RPL) should always be
illuminated and steady with the ignition ªONº and the
engine stopped. Ignition feed voltage is supplied to the
RPL bulb through the meter fuse. The powertrain control
module (PCM) orders the RPL ªONº signal for Multiplex
Control Unit. When Multiplex Control Unit is received RPL
ªONº signal that turn RPL ªONº by grounding the RPL
driver circuit.
The RPL should not remain ªONº with the engine running
and no DTC(s) set. A steady RPL with the engine running
and no DTC(s) suggests a short to ground in the RPL
driver circuit.
Diagnostic Aids
An intermittent RPL may be caused by a poor connection,
rubbed through wire insulation, or a wire broken inside the
insulation. Check for the following items:
Poor connection or damaged harness ± Inspect the
PCM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal to wire connection, and
damaged harness.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. If the RPL does not remain ªONº when the Multiplex
Control Unit is disconnected, the RPL driver wiring
is not faulty.
3. If the RPL driver circuit is OK, the instrument panel
cluster is faulty.
10. This vehicle is equipped with a PCM which utilizes
an electrically erasable programmable read only
memory (EEPROM). When the PCM is replaced,
the new PCM must be programmed. Refer to PCM
Replacement and Programming Procedures in
Powertrain Control Module (PCM) and Sensors.

6E±95
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Reduced Power Lamp (RPL) ªONº Steady

 
StepNo Ye s Value(s) Action
9Locate and repair the circuit between PCM and DLC.
Is the action complete?
ÐGo to Step 2Ð
10Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed.
Refer to ON-Vehicle Service in Power Control
Module and Sensors for procedures.
And also refer to latest Service Bulletin.
Check to see if the latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
Ð
Go to OBD
System
Check
Ð

6E±96
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Starter Control System Check
060R200062
Circuit Description
Starter control system is controlled by the Power Train
Control Module (PCM). The PCM monitors starter switch
signal (ªSTARTºposition ) and MODE switch (park or
neutral) signal. PCM is operated by the ignition switch.
Ignition feed voltage is supplied to the MODE switch and
starter relay through the engine fuse. PCM turns the
starter relay ªONº by grounding the starter relay driver
circuit.
The starter motor is operated until 30 seconds based on
starter relay signal.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Mis routed harness.
Rubbed through wire insulation.

Broken wire inside the insulation.
Test Description
2.If Anti-theft system is ªONº, PCM does not operate
starter control system.
19.Refer to
6D section.
21.Refer to 6D section.
24.This vehicle is equipped with a PCM which utilizes
an electrically erasable programmable read only
memory (EEPROM). When the PCM is replaced,the
new PCM must be programmed.
Refer to
PCM Replacement and Programming
Procedures in Powertrain Control Module (PCM) and
Sensors.
Starter Control System Check

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªAnti-theft Systemº normally? Refer to
Owner's Manual.ÐGo to Step 3Go to Step 7

6E±99
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Starter Control System Check

 
StepNo Ye s Value(s) Action
27Check the engine start times.
Is the engine start time less than specified value?
10 sec.System OK
Go to the
Engine
Cranks But
Will Not Run
Chart
28Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed.Refer to
ON-Vehicle Service in Power
ControlModule and Sensors
for procedures.And also
refer to latest Service Bulletin.Check to see if the latest
software is released ornot.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ

6E±102
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description
The electronic Ignition system uses a coil -at-plug method
of spark distribution. In this type of ignition system, the
powertrain control module (PCM) triggers the correct
driver outside the Ignition Current Sense System (ICSS),
which then triggers the correct ignition coil based on the
58X signal received from the crankshaft position sensor
(CKP). The spark plug connected to the coil fires when
the ICSS opens the ground circuit for the coil's primary
circuit.
During crank, the PCM monitors the CKP 58X signal. The
CKP signal is used to determine which cylinder will fire
first. After the CKP 58X signal has been processed by the
PCM, it will command all six injectors to allow a priming
shot of fuel for all the cylinders. After the priming, the
injectors are left ªOFFº during the next six 58X reference
pulses from the CKP. This allows each cylinder a chance
to use the fuel from the priming shot. During this waiting
been received by the PCM. The ION sensor signal allows
the PCM to operate the injectors sequentially based on
camshaft position. If the camshaft position signal is not
present at start - up, the PCM will begin sequential fuel
delivery with a 1 -in-6 chance that fuel delivery is correct.
The engine will run without a ION sensor signal, but will
set a DTC code.
Diagnostic Aids
An intermittent problem may be caused by a poor
connection, rubbed - through wire insulation or a wire
broken inside the insulation. Check for the following
items:

Poor connection or damaged harness-Inspect the
PCM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal-to-wire connection, and
damaged harness.

Faulty engine coolant temperature sensor-Using a
Tech 2, compare engine coolant temperature with
intake air temperature on a completely cool engine.
Engine coolant temperature should be within 10
C of
intake air temperature. If not, replace the ECT sensor.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
5. An obvious cause of low fuel pressure would be an
empty fuel tank.
6. The engine will easily start and run if a few injectors
are disabled. It is not necessary to test all injectors
at this time since this step is only a test to verify that
all of the injectors have not been disabled by fuel
contamination.
7. A blinking test light verifies that the PCM is
monitoring the 58X crankshaft reference signal and
is capable of activating the injectors. If there is an
open or shorted driver circuit, DTCs 201 ± 206 and
a misfire DTC 300 ± 306 should be set.
19. By using a spark tester, each ignition coil's ability to
produce 25,000 volts is verified.
25. If there is an open or shorted driver circuit, DTCs
201 ± 206 and a misfire DTC 301 ± 306 should be
set. All six injector driver circuits can be checked at
one time without removing the intake manifold if a J
39021 ± 95 test light is available. This is the
alternative procedure:

With the ignition ªOFFº, disconnect the gray
connector located at the rear of the air filter, attached
to a bracket on the purge canister.

Connect test light J 39021 ± 95 to the connector. Do
any of the light constantly illuminate or fail to blink
when the engine is cranked? If so, repair the short or
open circuit, or replace the PCM if indicated.
This procedure only tests the driver circuit as far as the
test connection, so step 31 is added to test the circuit all
the way to the injector.
Engine Cranks But Will Not Run

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Check the ignition coil fuse, the engine fuse, and the
PCM fuse.
Was a fuse blown?
ÐGo to Step 3Go to Step 4
3Check for a short to ground and replace the fuse.
Is the action complete?
ÐVerify repairÐ

6E±105
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run

 
StepNo Ye s Value(s) Action
23Refer to Engine Mechanical Diagnosis to diagnose the
following conditions:

Faulty or incorrect camshaft drive belts

Leaking or sticky valves or rings

Excessive valve deposits

Weak valve springs

Incorrect valve timing

Leaking head gasket
Is the action complete?
ÐVerify repairGo to Step 25
24Observe the ªEngine Speedº data display on the Tech 2
while cranking the engine.
Is the engine RPM indicated?
ÐGo to Step 25Go to Step 34
251. Disconnect the 7-pin gray connector at the rear of
the air filter beneath the point where the air duct
attaches to the MAF sensor.
2. Ignition ªONº.
3. Using a test light connected to ground, probe the
ignition terminal at the PCM (female) side of the
7-pin connector.
Is the test light ªONº?
ÐGo to Step 26Go to Step 32
261. At the PCM (female) side of the connector, connect
a test light between the ignition + terminal and one
of the injector driver circuits at the same connector.
2. Ignition ªONº.
3. Observe the test light, and repeat the test for each
injector driver circuit.
Did the test light stay on when checking any of the 6
injector driver circuits?
ÐGo to Step 27Go to Step 29
271. Ignition ªOFFº, disconnect the PCM.
2. Ignition ªONº, observe the test light.
Is the test light ªONº?
ÐGo to Step 28Go to Step 33
28Locate and repair the short to ground in the injector
driver circuit.
Is the action complete?
ÐVerify repairÐ
291. Using the same test location as in step 26, connect
a test light between the ignition terminal and one of
the driver circuits.
2. Crank the engine and observe the test light.
3. Repeat for each injector driver circuit.
Did the light blink during the test for each circuit?
ÐGo to Step 31Go to Step 30
30Check for an open injector driver circuit.
Was a problem found?
ÐVerify repairGo to Step 33

6E±106
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run

 
StepNo Ye s Value(s) Action
311. At the injector (male) side of the gray connector
mentioned in step 25, connect an ohmmeter
between the ignition pin and one of the driver circuit
pins.
2. Check for continuity in the circuit.
3. Repeat for each injector circuit. The readings
should be approximately equal to the specified
value for injector resistance.
Was a problem found?
12.5
Verify repairGo to Step 8
32Repair the ignition feed circuit.
Is the action complete?
ÐVerify repairÐ
33Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed.
Refer to
ON-Vehicle Service in Power Control Module
and Sensors for procedures.
And also refer to latest Service Bulletin.
Check to see if the latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ
341. Raise the vehicle and disconnect the CKP sensor
harness.
2. Ignition ªONº.
3. With a test light to ground, probe the harness
ignition feed terminal.
Did the light illuminate?
ÐGo to Step 36Go to Step 35
35Check the ignition feed wire between the sensor and
the PCM for a short to ground or open circuit.
Is the action complete?
ÐVerify repairÐ
361. Ignition ªONº.
2. At the CKP harness connector, connect a test light
between the ignition and ground terminals.
Did the light illuminate?
ÐGo to Step 38Go to Step 37
37Check the sensor ground circuit for an open or short to
voltage.
Is the action complete?
ÐVerify repairÐ
38Check the signal circuit between the sensor and the
PCM for a short to ground, short to voltage, or an open.
Was a problem found?
ÐVerify repairGo to Step 39
39Replace the CKP position sensor.
Is the action complete?
ÐVerify repairGo to Step 33

6E±110
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test

 
StepNo Ye s Value(s) Action
11Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ
121. Reconnect the fuel pump relay.
2. Disconnect the fuel pump electrical connector at the
fuel tank.
3. Using a test light connected to ground, probe the
fuel pump feed wire (harness side).
4. Command the fuel pump ªONº with a Tech 2.
Did the light illuminate for 2 seconds?
ÐGo to Step 15Go to Step 13
131. Honk the horn to verify that the horn relay is
functioning.
2. Substitute the horn relay for the fuel pump relay.
3. Leave the test light connected as in step 12.
4. Command the fuel pump ªONº with the Tech 2.
Did the test light illuminate for 2 seconds when the fuel
pump was commanded ªONº?
ÐGo to Step 17Go to Step 14
141. Re-connect the horn relay in its proper location.
2. Check for a short circuit, blown fuse or open circuit
between the relay and the fuel tank.
Is the action complete?
ÐVerify repairÐ
151. With the fuel pump electrical connector at the fuel
tank disconnected, connect a test light between the
feed wire and the ground wire (harness side).
2. Command the fuel pump ªONº with a Tech 2.
Did the test light illuminate for 2 seconds?
ÐGo to Step 18Go to Step 16
16Repair the open circuit in the fuel pump ground wire.
Is the action complete?
ÐVerify repairÐ
171. Re-connect the horn relay in its proper location.
2. Replace the fuel pump relay.
Is the action complete?
ÐVerify repairÐ
18Replace the fuel pump.
Is the action complete?
ÐVerify repairÐ

6E±112
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description

The powertrain control module (PCM) controls
engine speed by adjusting the position of the throttle
control valve (DC motor). The throttle motor is a DC
motor driven by one coil. The PCM applies current to
the DC motor coil in PWM (%) to adjust the throttle
valve into a passage in the throttle body to allow air
flow. This method allows highly accurate control of
engine speed and quick response to changes in
engine load.

The accelerator position (AP1) sensor circuit
provides a voltage signal relative to accelerator pedal
angle.
The accelerator pedal angle will vary about 13% at
idle position to about 87% at wide open
throttle(WOT).
APS signal is used to determine which DC motor will
adjust throttle position.
After the APS signal has been processed by the
PCM, it will command DC motor to allow movement
of throttle position.
Diagnostic Aids

An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside
the insulation. Check for poor connections or a
damaged harness. Inspect the PCM harness and
connector for improper mating, broken locks,
improperly formed or damaged terminals, poor
terminal-to-wire connection, and damaged harness.

Throttle body ± Check for objects blocking the DC
motor or throttle bore, excessive deposits in the ETC
passage and on the valve spring, and excessive
deposits in the throttle bore and on the throttle valve
plate.

Accelerator pedal ± Check for objects blocking the AP
sensor or pedal arm with spring, and excessive
deposits in the accelerator pedal arm and on the
accelerator pedal.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Visually/physically inspect for the following throttle
valve conditions.
3. Visually/physically inspect for the following
accelerator pedal conditions.
5. Check the following circuits for throttle valve and DC
motor. Check the following TP sensor resistance
and DC motor.
7. Check the following circuits for accelerator pedal.
Check the following AP sensor resistance.
10. Following DTC: Software detect Error for ETC
system.
11. Following DTC: Software detect Error for ETC
system.

6E±113
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Electric Throttle Control (ETC) System Check

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Visually/physically inspect for the following conditions:

Throttle body tampering.

Restricted intake throttle system. Check for a
possible collapsed air intake duct, restricted air
filter element, or foreign objects blocking the air
intake system.

Throttle body: Check for objects blocking the
throttle passage or throttle bore, excessive
deposits in the throttle passage and on the throttle
valve, and excessive deposits in the throttle bore
and on the throttle plate.

Throttle body with lever: When check for objects
to send round the throttle spring lever that lever is
smooth movement by less than 9 l´bm{1.0 N´m},
and spring lever has not excessive play.

Throttle function: Check for the throttle function.
When ignition switch ªONº that throttle lever is
smooth operated by step on the accelerator
pedal.
Did any of the above require a repair?
Ð
Refer to
appropriate
section for
on-vehicle
service
Go to Step 3
3Visually/physically inspect for the following conditions:

Accelerator pedal tampering.

Accelerator pedal : Check for objects blocking the
spring or pedal arm.

Accelerator pedal : For check for objects to move
the accelerator pedal that pedal is smooth
movement, and accelerator pedal arm has not
excessive play.
Did any of the above require a repair?
Ð
Refer to
appropriate
section for
on-vehicle
service
Go to Step 4
41. Check for a poor connection at the throttle body
harness connector.
2. Check for a poor connection at the accelerator
position sensor harness connector.
3. If a problem is found, replace faulty terminals as
necessary.
Was a problem found?
ÐVerify repairGo to Step 5
5Check the following circuits for an open, short to
voltage, short to ground, or poor connection at the
PCM:

Throttle position sensor 1 circuit.

Throttle position sensor 2 circuit.

Throttle DC motor circuit.

Throttle position sensor resistance.

Throttle DC motor resistance.
If a problem is found, repair as necessary.
Was a problem found?
Vcc±GND
1±7k

SIG±GND
change
resistance
0.3±100

Verify repairGo to Step 6