check engine ISUZU AXIOM 2002 Service Repair Manual

6E±303
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0402 ± EGR Pintle Crank Open Error

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº, review and record
Tech 2 Failure Records data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor ªDTCº info for DTC P0402
until the DTC P0402 test runs. Note the result.
Does the Tech 2 indicates DTC P0402 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
ÐGo to Step 4Go to Step 5
4Repair the damaged pin or terminal.
Is the action complete?
ÐVerify repairÐ
51. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any foreign
material between seat and pintle.
Was any foreign material in EGR valve?
ÐGo to Step 6Go to Step 7
61. Remove EGR valve foreign material from EGR
valve and clean up inside.
2. Visually inspect for damage of pintle and seat,
which leakage may occur.
Was there any severe damage which affects function?
ÐGo to Step 7
Verify repair
Go to
Step 8
71. Reconnect.
2. Ignition ªOFFº.
3. Install the Tech 2.
4. Run the engine at idle.
5. On Tech-II, select special function for EGR.
6. Use the ªUPº arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
ÐÐGo to Step 8
8Replace the EGR valve.
Does DTC P0402 still fail ªDTCº test on the Tech 2?
ÐGo to Step 9Verify repair
9Replace the PCM.
Is the action complete?
ÐVerify repairÐ

6E±304
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0404 EGR Open Stuck
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 pintle position is different from
commanded position. If the PCM detects a pintle position
signal indicates more than 15 points different between
current and commanded and more than 15 seconds, the
PCM will set DTC P0404.
Conditions for Setting the DTC

The engine is running.

Ignition voltage is between 11 and 16 volts.

Intake Air Temp is more than 3
C (37.4
F).

Desire EGR position is less than 3%.

The difference between desired EGR and current EGR
is less than 3%.

Difference EGR pintle position between current and
commanded position becomes more than 15% and
last more than 15 seconds, and this condition meets
three times in a trip. Then it trigger, the PCM lights on.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.
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 P0404 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0404 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 may
cause EGR stuck open or unsmooth operation. Those
carbon deposit may occur by unusual port operation.
Clean up carbon may make smooth function of EGR
valve.

Poor connection or damaged harness ± Inspect the
wiring harness for damage. If the harness appears to
be OK, observe the EGR actual position display on the
Tech 2 while moving connectors and wiring harnesses
related to EGR valve. A change in the display will
indicate the location of the fault.

6E±305
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0404 ± EGR Open Stuck

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor ªDTCº info for DTC P0404
until the DTC P0404 test runs. Note the result.
Does the Tech 2 indicates DTC P0404 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
ÐGo to Step 4Go to Step 5
4Repair the damaged pin or terminal.
ÐVerify repair
Is the action
complete?
51. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any excessive
carbon deposit on EGR shaft.
Was excessive carbon deposit on EGR valve shaft?
ÐGo to Step 6Go to Step 7
61. Clean up EGR valve shaft and inside of EGR valve.
2. Visually inspect damage of pintle and seat if is bent,
leakage may occur.
Was there any severe damage which affects function?
ÐGo to Step 8
Verify repair
Go to
Step 7
71. Reconnect.
2. Ignition ªOFFº.
3. Install the Tech 2.
4. Run the engine at idle.
5. On the Tech 2, select EGR Control Test.
6. Use the ªUPº arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
ÐÐGo to Step 8
8Replace the EGR valve.
Does DTC P0404 still fail ªDTCº test on the Tech 2?
ÐGo to Step 9Verify repair
9Replace 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

6E±306
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0405 EGR Low Voltage
060R200050
Circuit Description
The powertrain control module (PCM) monitors the EGR
valve pintle position input to ensure that the valve
responds properly to command from the PCM. If current
pintle position voltage indicates less than 0.1 V and last
more than 10 seconds, then the PCM will set DTC P0405.
Conditions for Setting the DTC

Ignition voltage is between 11 and 16 volts.

Intake Air Temp is more than 3
C (37.4
F).

EGR pintle position is less than 2% and last more than
10 sec. Action taken when the DTC sets.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.

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 P0402 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0405 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:

Poor connection or damaged harness ± Inspect the
wiring harness for damage. If the harness appears to
be OK, observe the EGR actual position display on the
Tech 2 while moving connectors and wiring harnesses
related to EGR valve. A change in the display will
indicate the location of the fault.

6E±307
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0405 ± EGR Low Voltage

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor ªDTCº info for DTC P0405
until the DTC P0405 test runs. Note the result.
Does the Tech 2 indicates DTC P0405 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
ÐGo to Step 4Go to Step 5
4Repair the damaged pin or terminal.
Is the action complete?
ÐVerify repairÐ
51. Disconnect the EGR harness connector.
2. Ignition ªONº.
3. At the EGR valve, use a DVM to check the voltage
at the 5 volt reference wire (BLU/RED) and ground.
Did the DVM indicate the specified value?
4±6 VGo to Step 6Go to Step 7
61. Disconnect the EGR harness connector.
2. Measure resistance between terminal 5 volt
reference wire and ground.
Was resistance in range?
5±5.5 K
Go to Step 10Go to Step 17
71. Ignition ªONº.
2. At the PCM connector, backprobe with a DVM at the
5 volt reference for the EGR valve.
Did the DVM indicate the specified value?
4±6 VGo to Step 8Go to Step 18
8Repair the open 5 volt reference circuit.
Is the action complete?
ÐVerify repairÐ
9Repair the damaged sensor ground wire.
Is the action complete?
ÐVerify repairÐ
101. Disconnect the EGR harness
2. Use an ohmmeter to measure between the pintle
position pin and the sensor ground pin on the EGR
valve.
NOTE: J-35616 Connector Test Adapter Kit may be
useful for gaining access to the recessed pins on the
valve.
Was the ohmmeter reading approximately equal to the
specified value?
1 to 1.25 K
Go to Step 13Go to Step 17
111. Ignition ªONº.
2. Backprobe with a DVM to measure voltage at EGR
valve pintle position pin and sensor ground pin.
Was voltage in range?
Less than
0.1 V
Go to Step 17Go to Step 12

6E±308
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0405 ± EGR Low Voltage

 
StepNo Ye s Value(s) Action
121. Ignition ªONº.
2. Backprobe with a DVM to measure voltage at PCM
sensor ground pin and pintle position pin.
Was voltage in range?
Less than
0.1 V
Go to Step 13Go to Step 18
131. Ignition ªOFFº.
2. Disconnect the EGR harness.
3. Check short circuit between EGR pintle position
circuit and EGR ground circuit.
Was any short circuit?
ÐGo to Step 14Go to Step 18
14Locate and repair the short to ground in the pintle
position circuit
Is the action complete?
ÐVerify repairÐ
151. Ignition ªOFFº.
2. Disconnect the PCM.
3. Ignition ªONº.
4. Measure the voltage between the EGR pintle
position circuit and ground.
Is the measured voltage near the specified value?
Less than
0.1 V
Go to Step 17Go to Step 16
16Check for a short circuit between other wires and the
pintle position circuit
Is there any short circuit?
Ð
Repair short
circuit and then
Verify repair
Go to Step 17
17Replace the EGR valve.
Does DTC P1404 still fail ªDTC test on the Tech 2?
ÐGo to Step 18Verify repair
18Examine the PCM pin and terminal connection.
Was there a damaged terminal?
ÐGo to Step 4Go to Step 19
19Replace 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

6E±309
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0406 EGR High Voltage
060R200050
Circuit Description
The powertrain control module (PCM) monitors the EGR
valve pintle position input to ensure that the valve
responds properly to command from the PCM. If current
pintle position voltage indicates more than 4.8 V and last
more than 10 seconds, then the PCM will set DTC P0406.
Conditions for Setting the DTC

Ignition voltage is between 11 and 16 volts.

Intake Air temp is more than 3
C (37.4
F).

EGR pintle position is more than 99% and last more
than 10 sec.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.

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 P0402 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0404 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:

Poor connection or damaged harness ± Inspect the
wiring harness for damage. If the harness appears to
be OK, observe the EGR actual position display on the
Tech 2 while moving connectors and wiring harnesses
related to EGR valve. A change in the display will
indicate the location of the fault.

6E±310
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0406 ± EGR High Voltage

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor ªDTCº info for DTC P0406
until the DTC P0406 test runs. Note the result.
Does the Tech 2 indicates DTC P0406 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
ÐGo to Step 4Go to Step 5
4Repair the damaged pin or terminal.
Is the action complete?
ÐVerify repair
Is the action
complete?
51. Disconnect the EGR harness connector.
2. Ignition ªONº.
3. At the EGR valve, use a DVM to check the voltage
at the 5 volt reference wire (BLU/RED).
Did the DVM indicate the specified value?
4±6 VGo to Step 8Go to Step 6
61. Ignition ªONº.
2. At the PCM connector, backprobe with a DVM at the
5 volt reference for the EGR valve.
Did the DVM indicate the specified value?
4±6 VGo to Step 7Go to Step 16
7Repair the open 5 volt reference circuit
Is the action complete?
ÐVerify repairÐ
81. Ignition ªOFFº
2. Disconnect the EGR harness.
3. Use a DVM to check for an resistance between 5 V
reference and Sensor Ground at EGR sensor
terminals.
NOTE: J-35616 Connector Test Adapter Kit may be
useful for gaining access to the recessed pins on the
valve.
Was the measured resistance in range?
5 to 5 K
Go to Step 9Go to Step 15
91. Ignition ªOFFº.
2. Disconnect the EGR harness.
3. Use a DVM to check for an resistance between
Sensor Ground and Signal Wire at EGR sensor
terminal.
Is there an open circuit?
ÐGo to Step 15Go to Step 10
101. Ignition ªOFFº.
2. Disconnect the EGR harness at PCM connector.
3. Use a DVM to check for shorted wire between S37
and F53.
Is there a shorted wire?
ÐGo to Step 14Go to Step 11

6E±311
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0406 ± EGR High Voltage

 
StepNo Ye s Value(s) Action
111. Ignition ªONº.
2. Use a DVM to backprobe at terminal Connector of
EGR valve for voltage.
Was measured voltage more than 4.8 V?
more than
4.8 V
Go to Step 12Go to Step 12
121. Ignition ªONº.
2. Stay the EGR harness connected.
3. Check voltage by backprobing at PCM S37
terminal.
Was voltage more than 4.8 V?
4.8 VGo to Step 16Go to Step 13
131. Locate short circuit at EGR harness between
BLU/RED to GRY/RED or GRY/RED to YEL,
BLU/RED.
2. Replace EGR harness.
Is the action complete?
ÐVerify repairÐ
14Replace EGR harness.
Is the action complete?
ÐVerify repairÐ
15Replace the EGR valve.
Does DTC P1404 still fail ªDTC test on the Tech 2?
ÐGo to Step 16Verify repair
16Replace 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

6E±312
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0420 TWC System Low Efficiency Bank 1
T321075
Circuit Description
To control emissions of hydrocarbons (HC), carbon
monoxide (CO), and oxides of nitrogen (NOx), a
three-way catalyst (TWC) is used. The catalyst promotes
a chemical reaction which oxidizes the HC and CO
present in the exhaust gas, converting them into
harmless water vapor and carbon dioxide. The catalyst
also reduces NOx, converting it to nitrogen. The
powertrain control module (PCM) has the ability to
monitor this process using the Bank 1 HO2S 1 and the
Bank 1 HO2S 2 heated oxygen sensors. The Bank 1
HO2S 1 sensor produces an output signal which indicates
the amount of oxygen present in the exhaust gas entering
the three-way catalytic converter. The Bank 1 HO2S 2
sensor produces an output signal which indicates the
oxygen storage capacity of the catalyst; this in turn
indicates the catalyst's ability to convert exhaust gases
efficiently. If the catalyst is operating efficiently, the Bank
1 HO2S 1 signal will be far more active than that produced
by the Bank 1 HO2S 2 sensor. If the PCM detects a level
of Bank 1 HO2S 2 activity that indicates the catalyst is no
longer operating efficiently, DTC P0420 will be set.
Conditions for Setting the DTC

No related DTCs.

The engine is operating in ªclosed loopº,

Engine air load is below 99%.

Engine coolant temperature is between 70
C (158
F)
and 120
C (248
F).

Mass air flow is between 2.5 g/second and 10
g/second.

Engine speed is below 200 RPM.

Catalyst temperature is above 350
C (662
F).

The PCM determines that the catalyst's oxygen
storage capacity is below the acceptable threshold.

Intake Air Temperature is between ±10
C (14
F) and
70
C (158
F).

Throttle angle is less than 1.5%.
Barometric Pressure is more than 72 kPa.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
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 P0420 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0420 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:

Poor connection at PCM ± Inspect harness connectors
for backed-out terminals, improper mating, broken
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
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.
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.
The ªTWC Monitor Test Counterº displayed on the Tech 2
may be used to monitor the progress of the TWC
diagnostic. To complete the TWC diagnostic with a good
catalyst, the counter must be allowed to increment to 49
samples and roll over to 0 at least twice. A failed catalyst