check engine light ISUZU AXIOM 2002 Service Manual PDF

6E±399
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
If it is determined that the DTC occurs intermittently,
performing the DTC P1120 Diagnostic Chart may
isolate the cause of the fault.
Diagnostic Trouble Code(DTC)P1120-TPS 1 Output Abnormal

StepActionValue(s)Ye sNo
1Was the ªOn-Board(OBD)System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine not running.
2. Observe the MAP reading on the Tech 2.
Is the MAP reading less than the specified value?
65kPaGo to Step 3Go to Step 6
31. 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 5V returns.)
ÐGo to Step 5Go to Step 4
41. 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 12
5Replace the MAP sensor.
Is the action complete?
ÐVerify repairÐ
6Observe 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?Throttle
Closed TPS1
8±10 % TPS2
8±10 % Wide
Open Throttle
TPS1 90±92
% TPS2
90±92 %
Refer to
Diagnostic
Aids
Go to Step 7
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 5Volt reference
circuit and the TP 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 signal circuit for a short to voltage.
2. TP1 sensor ground circuit for high resistance
between the PCM and the TP sensor.
3. TP1 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±402
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Rubbed through wire insulation.

Broken wire inside the insulation.
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
AP sensor 1, AP sensor 2, AP sensor 3 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 P1125 cannot be duplicated, the information
included in the Failure Records data can be useful in
determined vehicle mileage since the DTC was last
set.
If it is determined that the DTC occurs intermittently,
performing the DTC P1125 Diagnostic Chart may
isolate the cause of the fault.
DTC P1125 ± ETC Limit Performance Model

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 AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
AP sensor 1
=13 % AP
sensor 2, 3
=85 ~ 89 %
open throttle
AP sensor 1
=85 ~ 89 %
AP sensor 2
=11 ~ 15 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 Voltage supply
circuit and the AP1, AP2 AND AP3 sensor signal
circuit at the AP sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 7Go to Step 8
6Check the following items;
1. AP1, AP2 or AP3 signal circuit for a short to voltage.
2. AP1, AP2 or AP3 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP1, AP2 or AP3 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 9

6E±428
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
information included in the Failure Records data can
be useful in determined vehicle mileage since the
DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC
P1120 Diagnostic Chart may isolate the cause of the
fault.
DTC P1220-TPS 2 Circuit Fault

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 not running.
2. Observe the MAP reading on the Tech 2.
Is the MAP reading less than the specified value?
65 kPaGo to Step 4Go to Step 7
41. 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 5V returns.)
ÐGo to Step 6Go to Step 5
51. Check the MAP signal circuit between the PCM and
MAP ground circuit.
2. If the MAP signal circuit is open or shorted, repair as
necessary.
Was the MAP signal circuit open or shorted?
ÐVerify repairGo to Step 13
6Replace the MAP sensor.
Is the action complete?
ÐVerify repairÐ
7Observe 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 TPS1
8±10 % TPS2
8±10 % WTO
TPS1 90±92
% TPS2
90±92 %
Refer to
Diagnostic
Aids
Go to Step 8
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 5Volt reference
circuit and the 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±434
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1271 ± APS 1± 2 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
3Observe the AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
AP sensor 1
=13 % AP
sensor 2 =85
~ 89 % Wide
open throttle
AP sensor 1
=85 ~ 89 %
AP sensor 2
=11 ~ 15 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 V supply circuit
and the AP sensor signal circuit at the AP1, AP2
sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP1and AP2 signal circuit for a short to voltage.
2. AP1and AP2 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP1and AP2 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 9
7Check the following items;
1. AP1and AP2 signal circuit or 5 V supply circuit for a
poor connection.
2. AP1and AP2 signal circuit or 5 V supply circuit for
high resistance between the PCM and the AP1 and
AP2 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8

6E±437
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1272 ± APS 2 ± 3 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
3Observe the AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idleposition
AP sensor 2
=86 ~ 88 %
AP sensor 3
=86 ~ 88 %
Wide open
throttle AP
sensor 2 =12
~ 14 % AP
sensor 3 =32
~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 Voltage supply
circuit and the AP sensor signal circuit at the AP2
and AP3 sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP2 and AP3 signal circuit for a short to voltage.
2. AP2 and AP3 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP2 and AP3 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 9
7Check the following items;
1. AP2 and AP3 signal circuit or 5 voltage supply
circuit for a poor connection.
2. AP2 and AP3 signal circuit or 5 voltage supply
circuit for high resistance between the PCM and the
AP2 and AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8

6E±440
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1273 ± APS 1 ± 3 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
3Observe the AP angle reading on the Tech2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idleposition
AP sensor 1
=13 % AP
sensor 3 =85
~ 89 % Wide
open throttle
AP sensor 1
=85 ~ 89 %
AP sensor 3
=32 ~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 Voltage supply
circuit and the AP sensor signal circuit at the AP1
and AP3 sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP1 and AP3 signal circuit for a short to voltage.
2. AP1 and AP3 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP1 and AP3 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 9
7Check the following items;
1. AP1 and AP3 signal circuit or 5 voltage supply
circuit for a poor connection.
2. AP1 and AP3 signal circuit or 5 voltage supply
circuit for high resistance between the PCM and the
AP1 and AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8

6E±443
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1275 ± APS 1 Circuit Fault

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 AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
=12 ~ 14 %
Wide open
throttle =86
~ 88 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 Volt supply circuit
and the AP1 sensor signal circuit at the AP sensor
harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP1 signal circuit for a short to voltage.
2. AP1 sensor ground circuit for high resistance
between the PCM and the AP sensor.
3. AP1 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 9
7Check the following items;
1. AP1 signal circuit or 5 volt supply circuit for a poor
connection.
2. AP1 signal circuit or 5 volt supply circuit for high
resistance between the PCM and the AP1 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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

6E±445
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1280 - APS 2 Circuit Fault

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 AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
=86 ~ 88
%Wide open
throttle =12
~ 14 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 voltage supply
circuit and the AP2 sensor signal circuit at the AP
sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP2 signal circuit for a short to volt.
2. AP2 sensor ground circuit for high resistance
between the PCM and the AP sensor.
3. AP2 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 9
7Check the following items;
1. AP2 signal circuit or 5 volt supply circuit for a poor
connection.
2. AP2 signal circuit or 5 volt supply circuit for high
resistance between the PCM and the AP2 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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

6E±447
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1285 ± APS 3 Circuit Fault

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 AP angle reading on the Tech 2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
=86 ~ 88
%Wide open
throttle =32
~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 volt supply circuit
and the AP3 sensor signal circuit at the AP sensor
harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP3 signal circuit for a short to voltage.
2. AP3 sensor ground circuit for high resistance
between the PCM and the AP sensor.
3. AP3 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 9
7Check the following items;
1. AP3 signal circuit or 5 volt supply circuit for a poor
connection.
2. AP3 signal circuit or 5 voltage supply circuit for high
resistance between the PCM and the AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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

6E±449
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1290 - ETC Forced Idle 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 AP angle reading on the Tech2 while
slowly opening the throttle.
Does the AP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?Idle position
AP sensor 1
=12 ~ 14 %
AP sensor 2,
3 =86 ~ 88 %
Wide open
throttle AP
sensor 1 =86
~ 88 % AP
sensor 2 =12
~ 14 % AP
sensor 3 =32
~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 voltage supply
circuit and the AP1, AP2 and AP3 sensor signal
circuit at the AP sensor harness connector.
2. Observe the AP sensor reading on the Tech2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP1,AP2 and AP3 signal circuit for a short to
voltage.
2. AP1, AP2 and AP3 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP1, AP2 and AP3 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 9
7Check the following items;
1. AP1, AP2 and AP3 signal circuit or 5 volt supply
circuit for a poor connection.
2. AP1, AP2 and AP3 signal circuit or 5 volt supply
circuit for high resistance between the PCM and the
AP1, AP2 and AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9