check engine light ISUZU AXIOM 2002 Service Manual Online

6E±453
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1295 - ETC Power Management Mode

 
StepNo Ye s Value(s) Action
101. Connect a test light between the 5Volt reference ªAº
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
5VGo to Step 13Go to Step 12
11Check the following items;
1. TP1 and TP2 signal circuit for a short to voltage.
2. TP1 and TP2 sensor ground circuit for high
resistance between the PCM and the TP sensor.
3. TP1and TP2 sensor ground circuit for a poor
connection.
4. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 14
12Check the following items;
1. TP1and TP2 signal circuit or 5 volt reference circuit
for a poor connection.
2. TP1 and TP2 signal circuit or 5 volt reference circuit
for high resistance between the PCM and the
TP1and TP2 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 14
13Replace the TP sensor.
Is the action complete?
ÐVerify repairÐ
141. Start the engine.
2. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
Is the ªMAF Frequencyº below the specified value?
6 ~ 10 g/sGo to Step 15Go to Step 18
151. Ignition ªOFFº.
2. Disconnect the MAF sensor connector.
3. Ignition ªONº, engine idling.
4. Using a Tech 2, monitor ªMAF Frequencyº.
Does the Tech 2 indicate a ªMAF Frequencyº at the
specified value?
0g/sGo to Step 16Go to Step 17
16Replace the MAF sensor.
Is the action complete?
ÐVerify repairÐ
171. Check the MAF harness for incorrect routing near
high voltage components (solenoids, relays,
motors).
2. If incorrect routing is found, correct the harness
routing.
Was a problem found?
ÐVerify repairGo to Step 23
181. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
2. Quickly snap open throttle to wide open throttle
while under a road load and record value.
Does the Tech 2 indicate a ªMAF Frequencyº at the
specified value?
6 ~ 10 g/sGo to Step 16Go to Step 19

6E±456
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
TP sensor 1, TP sensor 2 display on the Tech 2 while
moving connectors and wiring harnesses related to the
sensor.
A change in the display will indicate the location of
the fault. If DTC P1299 cannot be duplicated, theinformation included in the Failure Records data can
be useful in determined vehicle mileage since the
DTC was last set.
If it is determining that the DTC occurs intermittently,
performing the DTC P1299 Diagnostic Chart may
isolate the cause of the fault.
DTC P1299 - ETC Forced Engine Shutdown Mode

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
3Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.
Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Closed
throttle TP
sensor 1 =8 ~
10 % TP
sensor 2 =90
~ 92 % Wide
open throttle
TP sensor 1
=90 ~ 92 %
TP sensor 2
=8 ~ 10 %
Go to Step 8Go to Step 4
41. Ignition ªOFFº.
2. Disconnect the DC motor.
Is the DC motor reading near the specified value?
0.3 ~ 100
Go to Step 5Go to Step 7
5Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.
Was a problem found?
ÐVerify repairGo to Step 6
6Check the throttle valve assembly.
Was a problem found?
Verify repairGo to Step 7
7Replace the DC motor. (Replace the Throttle valve
assembly)
Is the action complete?
ÐVerify repairGo to Step 8
81. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
0VGo to Step 9Go to Step 10
91. Connect a test light between the 5 Volt reference
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
5VGo to Step 12Go to Step 11

6E±474
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1404 EGR Stuck Closed
060R200050
Circuit Description
The powertrain control module (PCM) monitors the EGR
valve pintle position input to ensure that the valve
responds properly to commands from the PCM, and to
detect a fault if current pintle zero position is different from
the learned zero position. If the PCM detects a pintle
position signal indicates more than 30 % different
between current zero position and the learned zero
position for more than 5 seconds, and this condition exists
3 times during trip, then the PCM will set DTC P1404.
Conditions for Setting the DTC

Ignition voltage is between 11 and 16 volts.

Intake Air temp is more than 3
C.

Desired EGR position is more than 3 %.

Difference of EGR pintle position between current and
the learned zero is more than 30 % for more than 5
seconds, and exists three times to the above condition
during a trip the PCM will set DTC 1404. Then it trigger
the PCM light on.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after consecutive 2nd trip in which the fault is
detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in Failure
Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P1404 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1404 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:

Excessive carbon deposit on EGR valve shaft and/or
foreign material may cause the EGR valve not to fully
seat. The carbon deposit may occur by unusual port
operation. Remove foreign material and/or excessive
carbon deposit on EGR valve shaft and to allow the
EGR valve to be fully seated.

Poor connection or damaged harness ± Inspect the
wiring harness for damage.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

6E±482
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1514 - TPS-MAF Correlation Error

 
StepNo Ye s Value(s) Action
101. Disconnect the MAP sensor.
2. Connect a test 5 volt reference circuit and the MAP
signal at the MAP sensor harness connector.
3. Observe the MAP reading on the Tech 2.
Is the MAP reading less than the specified value? (If no,
start with diagnosis chart for other sensors in the circuit
and see if 5Vreturns.)
ÐGo to Step 11Go to Step 12
111. Check the MAP signal circuit between the PCM and
MAP ground circuit.
2. If the MAP signal circuit is open or shorted, repair it
as necessary.
Was the MAP signal circuit open or shorted?
ÐVerify repairGo to Step 13
12Replace the MAP sensor.
Is the action complete?
ÐVerify repairÐ
13Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.
Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Closed
throttle TP
sensor 1 =8 ~
10 % TP
sensor 2 =90
~ 92 % Wide
open throttle
TP sensor 1
=90 ~ 92 %
TP sensor 2
=8 ~ 10 %
Refer to
Diagnostic
Aids
Go to Step 14
141. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech2.
Is the TP sensor reading near the specified value?
0VGo to Step 15Go to Step 16
151. Connect a test light between the 5Volt reference
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech2.
Is the TP sensor reading near the specified value?
5VGo to Step 18Go to Step 17
16Check the following items;
1. TP1 and TP2 signal circuit for a short to voltage.
2. TP1 and TP2 sensor ground circuit for high
resistance between the PCM and the TP sensor.
3. TP1 and TP2 sensor ground circuit for a poor
connection.
4. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 19

6E±485
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
moving connectors and wiring harnesses related to the
sensor.
A change in the display will indicate the location of
the fault. If DTC P1515 cannot be duplicated, the
information included in the Failure Records data canbe useful in determing vehicle mileage since the
DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC P1515 Diagnostic Chart may
isolate the cause of the fault.
DTC P1515 - Command - Actual TPS Correlation Error

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
31. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ª DTCº info for DTC P1515.
Does the Tech 2 indicate DTC P1515 failed this
ignition?
ÐGo to Step 4
Refer to
Diagnostic
Aids
4Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.
Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Closed
throttle TP
sensor 1 =8 ~
10 % TP
sensor 2 =90
~ 92 % Wide
open throttle
TP sensor 1
=90 ~ 92 %
TP sensor 2
=8 ~ 10 %
Go to Step 5Go to Step 8
51. Ignition ªOFFº.
2. Disconnect the DC motor.
Is the DC motor reading near the specified value?
0.3 ~ 100
Go to Step 6Go to Step 7
6Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.
Was a problem found?
ÐVerify repairGo to Step 8
7Replace the DC motor.
Is the action complete?
ÐVerify repairGo to Step 6
81. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
0VGo to Step 9Go to Step 10
91. Connect a test light between the 5Volt reference
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech2.
Is the TP sensor reading near the specified value?
5VGo to Step 12Go to Step 11

6E±488
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
information included in the Failure Records data can
be useful in determining vehicle mileage since the
DTC was last set.If it is determined that the DTC occurs intermittently,
performing the DTC P1516 Diagnostic Chart may
isolate the cause of the fault.
DTC P1516 - Command - Actual TPS Correlation Error

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
31. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ªDTCº info for DTC P1516.
Does the Tech 2 indicate DTC P1516 failed this
ignition?
ÐGo to Step 4
Refer to
Diagnostic
Aids
4Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.
Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Closed
throttle TP
sensor 1 =8 ~
10 % TP
sensor 2 =90
~ 92 % Wide
open throttle
TP sensor 1
=90 ~ 92 %
TP sensor 2
=8 ~ 10 %
Go to Step 5Go to Step 8
51. Ignition ªOFFº.
2. Disconnect the DC motor.
Is the DC motor reading near the specified value?
0.3 ~ 100
Go to Step 6Go to Step 7
6Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.
Was a problem found?
ÐVerify repairGo to Step 8
7Replace the DC motor.
Is the action complete?
ÐVerify repairGo to Step 6
81. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech2.
Is the TP sensor reading near the specified value?
0VGo to Step 9Go to Step 10
91. Connect a test light between the 5 Volt reference
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
5VGo to Step 12Go to Step 11

6E±491
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
If it is determined that the DTC occurs intermittently,
performing the DTC P1523 Diagnostic Chart may
isolate the cause of the fault.
DTC P1523 - Actuator Control Return Performance

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
3Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.
Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Closed
throttle TP
sensor 1 =8 ~
10 % TP
sensor 2 =90
~ 92 % Wide
open throttle
TP sensor 1
=90 ~ 92 %
TP sensor 2
=8 ~ 10 %
Go to Step 4Go to Step 7
41. Ignition ªOFFº.
2. Disconnect the DC motor.
Is the DC motor reading near the specified value?
0.3 ~ 100
Go to Step 5Go to Step 6
5Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.
Was a problem found?
ÐVerify repairGo to Step 7
6Replace the DC motor.
Is the action complete?
ÐVerify repairGo to Step 5
71. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
0VGo to Step 8Go to Step 9
81. Connect a test light between the 5 Volt reference
circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
5VGo to Step 11Go to Step 10
9Check the following items;
1. TP1 and TP2 signal circuit for a short to voltage.
2. TP1 and TP2 sensor ground circuit for high
resistance between the PCM and the TP sensor.
3. TP1and TP2 sensor ground circuit for a poor
connection.
4. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 12

6E±493
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1571 Brake Switch No Operation
060R200067
Circuit Description
The brake switch has 3 functions.

Brake pedal operation check

Brake light operation (On and off)

Cruise control (Cancel)
The PCM receives vehicle speed and switch position
signals from the brake switch. The PCM sets brake
operating conditions in response to these signals.
If the brake switch is on, the brake system is in normal
operation (cruise control cancelled).
Conditions for Setting the DTC

Two break switch signals do not acknowledge after
signal changed.

Switch does not change during accelerating vehicle or
decelerating.

VSS is not fault.

Engine is running.
Action Taken When the DTC Sets

The PCM will not turn the malfunction indicator lamp
(MIL) ªONº.

The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the DTC

DTC P1571 can be cleared by using the scan tool
ªClear Infoº function or by disconnecting the PCM
battery feed.
Diagnostic Aids

Damaged harness±Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
fuel level display on the scan tool while moving
connectors and wiring harnesses related to the sensor.
A change in the display will indicate the location of the
fault.

6E±495
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1625 PCM Unexpected Reset
Circuit Description
The powertrain control module (PCM) monitors
unexpected PCM reset. This will not turn on MIL light on,
only record code DTC P1625.
Conditions for Setting the DTC

Clock or COP (Computer Operating Properly) reset.
Action Taken When the DTC Sets

The PCM will not illuminate the malfunction indicator
lamp (MIL).

The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P1625 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1625 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:

P1625 stored alone does not need diagnosis. Clear
DTC code.
DTC P1625 ± PCM Unexpected Reset

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition is ªONº.
2. Install the Tech 2.
3. Start the engine and let it Idle.
4. On the Tech 2, select ªDTC infoº.
Does the Tech 2 indicate DTC P1625 failed?
ÐGo to Step 3
Go to
Diagnostic
Aids
31. Ignition is ªONº.
2. Clear DTC P1625 by using the Tech 2 ªClear Infoº.
3. Start the engine and let it Idle.
4. On the Tech 2, select ªDTC infoº.
Does the Tech 2 indicate DTC P1625 failed?
ÐGo to Step 4
Go to
Diagnostic
Aids
41. Check for aftermarket electronics, such as
transceiver, stereos, and anti theft devices. They
may radiate EMI into the control system if they are
improperly installed. (This may cause a false sensor
reading and turn on the MIL.)
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairÐ

6E±506
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Symptom Diagnosis
Preliminary Checks
Before using this section, perform the ªOn-Board
Diagnostic (OBD) System Checkº and verify all of the
following items:

The powertrain control module (PCM), and
malfunction indicator lamp (MIL) (Check Engine
lamp) and Reduced Power Lamp (RPL) are operating
correctly.

There are no DTC(s) stored.

Tech 2 data is within normal operating range. Refer to
Typical Scan Data Values.

Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
Visual/Physical Check
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time.
This check should include the following items:

PCM grounds for cleanliness, tightness and proper
location.

Vacuum hoses for splits, kinks, and proper
connections, as shown on the ªVehicle Emission
Control Informationº label. Check thoroughly for any
type of leak or restriction.

Air intake ducts for collapsed or damaged areas.

Air leaks at throttle body mounting area, mass air flow
(MAF) sensor and intake manifold sealing surfaces.

Ignition components for cracking, hardness, and
carbon tracking.

Wiring for proper connections, pinches and cuts.
Intermittents
IMPORTANT:An intermittent problem may or may not
turn on the malfunction indicator lamp (MIL) or store a
DTC. DO NOT use the Diagnostic Trouble Code (DTC)
charts for intermittent problems. The fault must be
present to locate the problem.
Most intermittent problems are caused by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions:

Poor mating of the connector halves or a terminal not
fully seated in the connector (backed out).

Improperly formed or damaged terminal.

All connector terminals in the problem circuit should
be carefully checked for proper contact tension.

Poor terminal-to-wire connection. This requires
removing the terminal from the connector body to
check.
Road test the vehicle with a J 39200 Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Use a Tech 2 to help detect intermittent conditions. The
scan tool has several features that can be used to locatean intermittent condition. Use the following feature to find
intermittent faults:

Using a Tech 2's ªFreeze Frameº buffer or ªFailure
Recordsº buffer can aid in locating an intermittent
condition. Review and record the information in the
freeze frame or failure record associated with the
intermittent DTC being diagnosed. The vehicle can
be driven within the conditions that were present
when the DTC originally set.
To check for loss of diagnostic code memory, disconnect
the MAP sensor and idle the engine until the MIL (Check
Engine lamp) comes on. DTC P0107 should be stored
and kept in memory when the ignition is turned ªOFFº. If
not, the PCM is faulty. When this test is completed, make
sure that you clear the DTC P0107 from memory.
An intermittent MIL (Check Engine lamp) with no stored
DTC may be caused by the following:

Ignition coil shorted to ground and arcing.

MIL (Check Engine lamp) wire to PCM shorted to
ground.

Poor PCM grounds. Refer to the PCM wiring
diagrams.
Check for improper installation of electrical options such
as lights, cellular phones, etc. Check all wires from the
PCM to the ignition coils for poor connections.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in
Electrical Diagnosis).
If problem has not been found, refer to
PCM Connector
Symptom
tables.

Check the ªCalibration IDº of the PCM, and compare it
with the latest Isuzu service bulletins and/or Isuzu
EEPROM reprogramming equipment to determine if
an update to the PCM's reprogrammable memory
has been released. To check the ªCalibration IDº,
connect the Tech 2, then look for ªPowertrainº, then
select ªCalibration IDº. This identifies the contents of
the reprogrammable software and calibration
contained in the PCM. If the ªCalibration IDº is not the
most current available, it is advisable to reprogram
the PCM's EEPROM memory, which may either help
identify a hard-to-find problem or may fix the problem.

Calibration ID (example)
Part number 9377709
Broadcast Code CYYD
Identifier 801