2002 ISUZU AXIOM engine coolant

6E±346
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0462 Fuel Level Sensor Circuit±Low Voltage
060RY00163
Circuit Description
The fuel level sensor is an important input to powertrain
control module (PCM) for the enhanced evaporative
system diagnostic. Fuel level information is needed for
the PCM to know the volume of fuel in the tank. The fuel
level affects the rate of change in air pressure in the
evaporative system. Several of the enhanced
evaporative system diagnostic sub-tests are dependent
upon correct fuel level information. The diagnostic will not
run when the tank is more than 85% or less than 15% full.
Fuel level DTCs should be diagnosed before other
evaporative system DTCs because they can cause other
DTCs to be set.
The sending unit is a float in the fuel tank which moves a
wiper arm across a variable resistor. Low fuel level
causes high resistance in the sending unit, and this is
recognized by the PCM because the circuit operates at a
corresponding low voltage. When the circuit is
continuously open or has a high resistance connection,
DTC P0462 is set.
Conditions for Setting the DTC

Fuel tank level ªslosh testº is completed.

Fuel tank level ªmain testº is completed.

Fuel tank level data is valid.

Fuel tank level signal is less than a specified value.

There are 100 test failures within a 200-test sample.
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 the
Failure Records data.
Conditions for Clearing the DTC

The PCM will turn the MIL ªOFFº after three
consecutive trips without a fault condition present. A
history DTC will be cleared if no fault conditions have
been detected for 40 warm-up cycles (engine coolant
temperature has risen 4
C (40
F) from the start-up
ECT, and ECT exceeds 71
C (160
F) during that
same ignition cycle).

DTC P0462 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±349
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0463 Fuel Level Sensor Circuit±High Voltage
060RY00163
Circuit Description
The fuel level sensor is an important input to powertrain
control module (PCM) for the enhanced evaporative
system diagnostic. Fuel level information is needed for
the PCM to know the volume of fuel in the tank. The fuel
level affects the rate of change in air pressure in the
evaporative system. Several of the enhanced
evaporative system diagnostic sub-tests are dependent
upon correct fuel level information. The diagnostic will not
run when the tank is more than 85% or less than 15%, full.
Fuel level DTCs should be diagnosed before other
evaporative system DTCs because they can cause other
DTCs to be set.
The sending unit is a float in the fuel tank which moves a
wiper arm across a variable resistor. High fuel level
causes low resistance in the sending unit. This is
recognized by the PCM because the circuit operates at a
corresponding high voltage. When the circuit is
continuously shorted to a voltage source greater than a
specified value, or when the 5 volt signal is shorted to
ground, DTC P0463 is set.
Conditions for Setting the DTC

Fuel tank level ªslosh testº is completed.

Fuel tank level ªmain testº is completed.

Fuel tank level data is valid.

Fuel tank level signal is greater than a specified value.

There are 100 test failures within a 200-test sample.
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 the
Failure Records data.
Conditions for Clearing the DTC

The PCM will turn the MIL ªOFFº after three
consecutive trips without a fault condition present. A
history DTC will be cleared if no fault conditions have
been detected for 40 warm-up cycles (engine coolant
temperature has risen 4
C (40
F) from the start-up
ECT, and ECT exceeds 71
C (160
F) during that
same ignition cycle) or the scan tool clearing function
has been used.

DTC P0463 can be cleared by using the scan tool
ªClear Infoº function or by disconnecting the PCM
battery feed.

6E±356
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0506 Idle Air Control System Low RPM
060R200057
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 position (%) to adjustment the throttle valve into a
passage in the throttle body to air flow. This method
allows highly accurate control of engine speed and quick
response to changes in engine load.
If the PCM detects a condition where too low of an idle
speed is present and the PCM is unable to adjust idle
speed by increasing the throttle position, DTC P0506 will
set, indicating a problem with the idle control system.
Conditions for Setting the DTC

No TPS, VSS, ECT, EGR, MAF, MAP, IAT, low voltage,
fuel system, canister purge, injector control, or ignition
control DTCs are set.

MAP is less than 60 kPa.

Canister purge duty cycle is above 10%.

Engine running time is more than 125 seconds.

Vehicle speed is less than 1 mph.

Engine coolant temperature (ECT) is above 50
C
(122
F).

Ignition voltage is between 9.5 volts and 16.7 volts.

The throttle is closed.

EVAP purge duty cycle more than 10%.

All conditions are met for 10 seconds.

Barometric pressure is more than 74.5 kPa.
Engine speed is more than 100-200 RPM lower than
desired idle based upon coolant temperature.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive 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 the
Failure Records data.
Conditions for Clearing the MIL/DTC

DTC P0506 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 or throttle DC motor ± 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.

Restricted air intake 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 ETC
passage or throttle bore, excessive deposits in the

6E±359
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0507 Idle Air Control System High RPM
060R200057
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 position (%) to adjustment the throttle valve into a
passage in the throttle body to air flow. This method
allows highly accurate control of engine speed and quick
response to changes in engine load.
If the PCM detects a condition where too high of an idle
speed is present and the PCM is unable to adjust idle
speed by increasing the throttle position, DTC P0507 will
set, indicating a problem with the idle control system.
Conditions for Setting the DTC

No TPS, VSS, ECT, EGR, MAF, MAP, IAT, low voltage,
fuel system, canister purge, injector control or ignition
control DTCs are set.

Barometric pressure is above 75 kPa.

Canister purge duty cycle is above 10%.

Engine running time is more than 125 seconds.

Vehicle speed is less than 1 mph.

Engine coolant temperature (ECT) is above 50
C
(122
F).

Ignition voltage is between 9.5 volts and 16.7 volts.

The throttle is closed.

EVAP purge duty cycle is more than 10%.
All conditions are met for 10 seconds.

Engine speed is more than 100-200 RPM higher than
desired idle based upon coolant temperature.

Barometric pressure is more than 74.5 kPa.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive 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 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 P0507 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0507 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 or throttle DC motor ± Inspect
harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed or

6E±388
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1111 IAT Sensor Circuit Intermittent High Voltage
D06RY00147
Circuit Description
The intake air temperature (IAT) sensor is a thermistor
which measures the temperature of the air entering the
engine. The powertrain control module (PCM) applies 5
volts through a pull-up resistor to the IAT sensor. When
the intake air is cold, the sensor resistance is high and the
PCM will monitor a high signal voltage on the IAT signal
circuit. If the intake air is warm, the sensor resistance is
lower causing the PCM to monitor a lower voltage. DTC
P1111 will set when the PCM intermittently detects an
excessively high signal voltage on the intake air
temperature sensor signal circuit.
Conditions for Setting the DTC

The engine has been running for over 30 seconds.

Vehicle speed is less than 32 km/h (20 mph).

Engine coolant temperature is above 60
C (140
F).

Mass air flow is less than 20g/second.

IAT signal voltage indicates and intake air temperature
intermittently less than ±39
C (±38
F) (about 5 volts)
for approximately 2.5 seconds over a 25-second
period of time.
Action Taken When the DTC Sets

The PCM will substitute a default value for intake air
temperature.
The PCM will store conditions which were present
when the DTC set as Failure Records data only. This
information will not be stored as Freeze Frame data.

DTC P1111 does not illuminate the MIL.
Conditions for Clearing the MIL/DTC

A history DTC P1111 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D T C P 1111 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
IAT display on the Tech 2 while moving connectors and
wiring harnesses related to the IAT sensor. A change
in the IAT 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.

6E±393
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1114 ECT Sensor Circuit Intermittent Low Voltage
060R200053
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in the engine coolant stream. The
powertrain control module (PCM) applies a voltage
(about 5.0 volts) through a pull-up resistor to the ECT
signal circuit. When the engine coolant is cold, the sensor
(thermistor) resistance is high, therefore the PCM will
measure a high signal voltage. As the engine coolant
warms, the sensor resistance becomes less, and the
ECT signal voltage measured at the PCM drops. With a
fully warmed up engine, the ECT signal voltage should
measure about 1.5 to 2.0 volts. If the PCM detects an
ECT signal that is intermittently below the range of the
ECT sensor, DTC P1114 will set.
Conditions for Setting the DTC

Engine run time longer than 120 seconds.

The ECT sensor signal is intermittently greater than
150
C (302
F) (about 0.10 volt) for a total of 10
seconds over a 100-second period.
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 set as Failure Records data only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC

A history DTC P1114 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1114 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
ECT display on the Tech 2 while moving connectors
and wiring harnesses related to the ECT sensor. A
change in the ECT 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

6E±394
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
Engine Coolant Temperature Sensor

C
FOHMS
Temperature vs. Resistance Values
(approximate)
100212177
80176332
60140667
4511 31188
35951802
25772796
15594450
5417280
±52312300
±15521450
±30±2252700
±40±40100700
DTC P1114 ± ECT Circuit Intermittent Low Voltage

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Is DTC P0117 also set?
Ð
Go to DTC
P0117
firstGo to Step 3
31. Check the ECT signal circuit between the ECT
sensor connector and the PCM for an intermittent
short to ground.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repair
Refer to
Diagnostic
Aids

6E±395
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1115 ECT Sensor Circuit Intermittent High Voltage
060R200053
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in the engine coolant stream. The
powertrain control module (PCM) applies a voltage
(about 5.0 volts) through a pull-up resistor to the ECT
signal circuit. When the engine coolant is cold, the sensor
(thermistor) resistance is high, therefore the PCM will
measure a high signal voltage. As the engine coolant
warms, the sensor resistance becomes less, and the
ECT signal voltage measured at the PCM drops. With a
fully warmed up engine, the ECT signal voltage should
measure about 1.5 to 2.0 volts. If the PCM detects an
ECT signal that is intermittently above the range of the
ECT sensor, DTC P1115 will set.
Conditions for Setting the DTC

Engine running time longer than 90 seconds.

The ECT sensor signal is intermittently greater than
±39
C (±38
F) (about 5 volts) for a total of 10 seconds
over a 100-second period.
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 data only.
This information will not be stored as Freeze Frame
data.
Conditions for Clearing the MIL/DTC

A history DTC P1115 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1115 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
ECT display on the Tech 2 while moving connectors
and wiring harnesses related to the ECT sensor. A
change in the ECT 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