2002 ISUZU AXIOM change time

6E±158
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0118 ECT Sensor Circuit High Voltage
060R200053
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in on a coolant crossover pipe at the
front of the engine. The powertrain control module (PCM)
applies a voltage (about 5 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.
Conditions for Setting the DTC

Engine running time is longer than 90 seconds.

The ECT sensor signal indicates an engine coolant
temperature of ±39
C (±38
F) or less (about 5 volts)
for a total of 50 seconds over a 100-second period.
Action Taken When the DTC Sets

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

The PCM will substitute the ECT reading with a default
engine coolant temperature value. The default value
is based on start-up intake air temperature and running
time.

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 P0118 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0118 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:
The ECT shares a ground with the Transmission Fluid
Temperature sensor, the Fuel Tank Pressure sensor, and
the MAP sensor.
Check the ground if these DTCs are also set.

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.
If DTC P0118 cannot be duplicated, the 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,

6E±162
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
DTC P0125 set indicates a faulty ECT sensor.
Comparing the engine coolant temperature displayed on
a Tech 2 with actual coolant temperature measured with a
thermometer may isolate this condition. If the displayed
engine coolant temperature is not close to the actual
coolant temperature, replace the ECT sensor.
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.
If DTC P0125 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage wince the DTC was last set.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Comparing the engine coolant temperature displayed
on a Tech 2 with actual coolant temperature
measured with a thermometer may isolate this
condition. If the displayed engine coolant
temperature is not close to the actual coolant
temperature, replace the ECT sensor. If the
temperatures are close, the fault is intermittent;
refer to
Diagnostic Aids.
Engine Coolant Temperature

C
FOHMS
Temperature vs. Resistance Values
(approximate)
100212177
80176332
60140667
4511 31188
35951802
25772796
15594450
5417280
±52312300
±15521450
±30±2252700
±40±40100700
DTC P0125 ±ECT Excessive Time to Closed Loop Fuel Control

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any ECT sensor DTCs set?
Ð
Go to
applicable
ECT sensor
DTC chart
Go to Step 3
31. Allow the engine to cool completely.
2. Check the cooling system coolant level (refer to
Cooling and Radiator).
Is the coolant level OK?
ÐGo to Step 4Go to Step 9
41. Start the engine.
2. With the engine idling, monitor ªENG COOL TEMPº
display on the Tech 2.
Does ªENG COOL TEMPº increase to above the
specified value within 2 minutes?
21
C (70
F)
Refer to
Diagnostic
Aids
Go to Step 5
5Check for proper operation of the thermostat (refer to
Cooling and Radiator).
Is the thermostat operating correctly?
ÐGo to Step 6Go to Step 9

6E±172
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0133 HO2S Slow Response Bank 1 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) continuously
monitors the heated oxygen sensor (HO2S) activity for 90
seconds after ªclosed loopº has been enabled. During the
monitoring period the PCM counts the number of times
that a rich-to-lean and lean-to-rich response is indicated
and adds the amount of time it took to complete all
rich-to-lean transitions and lean-to-rich transitions. With
this information, an average time for rich-to-lean and
lean-to-rich transitions can be determined. If the average
response time of either transition is too slow, a DTC
P0133 will be set.
A lean-to-rich transition is indicated when the HO2S
voltage changes from less than 300 mV to greater than
600 mV. A rich-to-lean transition is indicated when the
HO2S voltage changes from more than 600 mV to less
than 300 mV. An HO2S that responds too slowly is likely
to be faulty and should be replaced.
Conditions for Setting the DTC

No related DTCs.

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

Engine is operating in ªclosed loopº.

Engine has been running for at least 90 seconds.

Engine speed is between 1500 RPM and 3000 RPM.

Canister purge duty cycle is greater than 2%.
Mass air flow is between 18 g/second and 42 g/second.

All above conditions are met for 3 seconds.

90 seconds after ªclosed loopº has been enabled,
Bank1 HO2S 1 average transition time between
300 mV and 600 mV is too slow. The lean-to-rich
average transition response time was longer than 94
milliseconds or rich-to-lean average transition
response time was longer than 105 milliseconds.
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.

ªOpen loopº fuel control will be in effect.
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 P0133 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0133 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.

6E±173
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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
Bank 1 HO2S 1 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 P0133 cannot be duplicated, 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.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is currently present.
3. HO2S transition time, ratio mean volts and switching
DTCs set for multiple sensors indicate probable
contamination. Before replacing the sensors,
isolate and correct the source of the contamination
to avoid damaging the replacement sensors.

6E±179
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0135 HO2S Heater Circuit Bank 1 Sensor 1
060R200054
Circuit Description
Heated oxygen sensors are used to minimize the amount
of time required for ªclosed loopº fuel control operation
and to allow accurate catalyst monitoring. The oxygen
sensor heater greatly decreases the amount of time
required for fuel control sensors Bank 1 HO2S 1 and Bank
2 HO2S 1 to become active. Oxygen sensor heaters are
required by post-catalyst monitor sensors to maintain a
sufficiently high temperature which allows accurate
exhaust oxygen content readings further from the engine.
The powertrain control module (PCM) will run the heater
test only after a cold start (determined by engine coolant
and intake air temperature at the time of start-up) and only
once during an ignition cycle. When the engine is started
the PCM will monitor the HO2S voltage. When the HO2S
voltage indicates a sufficiently active sensor, the PCM
looks at how much time has elapsed since start-up. If the
PCM determines that too much time was required for the
Bank 1 HO2S 1 to become active, a DTC P0135 will set.
The time it should take the HO2S to reach operating
temperature is based on the accumulated amount of air
that has passed through the MAF sensor and into the
engine (more accumulated air flow = shorter time to
HO2S activity).
Conditions for Setting the DTC

The engine has been running for over 120 seconds.

Heater signal is below 0.1A.

Bank 1 HO2S 1 voltage does not change more than
150 mV from the bias voltage (between 400 mV and
500 mV) for a longer amount of time than it should. The
maximum amount of time to come up to operating
range is 150 seconds. This warm-up time depends on
the engine coolant temperature at start-up and
accumulate air flow since start-up.
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 P0135 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0135 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.

6E±191
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0141 HO2S Heater Circuit Bank 1 Sensor 2
060R200054
Circuit Description
Heated oxygen sensors are used to minimize the amount
of time required for closed loop fuel control operation and
to allow accurate catalyst monitoring. The oxygen sensor
heater greatly decreases the amount of time required for
fuel control sensors Bank 1 HO2S 1 and Bank 2 HO2S 1
to become active. Oxygen sensor heaters are required
by post-catalyst monitor sensors to maintain a sufficiently
high temperature which allows accurate exhaust oxygen
content readings further from the engine.
The powertrain control module (PCM) will run the heater
test only after a cold start (determined by engine coolant
and intake air temperature at the time of start-up) and only
once during an ignition cycle. When the engine is started
the PCM will monitor the HO2S voltage. When the Bank
HO2S voltage indicates a sufficiently active sensor, the
PCM looks at how much time has elapsed since start-up.
If the PCM determines that too much time was required
for the Bank 1 HO2S 2 to become active, a DTC P0141
will set. The time it should take the HO2S to reach
operating temperature is based on the total amount of air
that has passed through the MAF sensor and into the
engine (more total airflow = shorter time to HO2S
activity).
Conditions for Setting the DTC

No related DTCs.

The engine has been running for over 120 seconds.
Ignition voltage is between 11 volts and 18 volts.

Bank 1 HO2S 2 voltage does not change more than
150 mV from the bias voltage (between
400 mV±500 mV) for a longer amount of time than it
should. The maximum amount of time to come up to
operating range is 120 seconds. This warm-up time
depends on the engine coolant temperature at start-up
and accumulated air flow since start-up.
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 P0141 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0141 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:

6E±200
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0153 HO2S Slow Response Bank 2 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) continuously
monitors the heated oxygen sensor (HO2S) activity for 90
seconds after ªclosed loopº has been enabled. During the
monitoring period the PCM counts the number of times
that a rich-to-lean and lean-to-rich response is indicated
and adds the amount of time it took to complete all
rich-to-lean transitions and lean-to-rich transitions. With
this information, an average time for rich-to-lean and
lean-to-rich transitions can be determined. If the average
response time of either transition is too slow, a DTC
P0153 will be set.
A lean-to-rich transition is indicated when the HO2S
voltage changes from less than 300 mV to greater than
600 mV. A rich-to-lean transition is indicated when the
HO2S voltage changes from more than 600 mV to less
than 300 mV. An HO2S that responds too slowly is likely
to be faulty and should be replaced.
Conditions for Setting the DTC

No related DTCs.

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

The engine is operating in ªclosed loopº.

Engine has been running for over 60 seconds.

Canister purge duty cycle is above 2%.

Engine speed is between 1500 RPM and 3000 RPM.
Mass air flow is between 18 g/second and 42 g/second.

All above conditions are met for 3 seconds.

90 seconds after ªclosed loopº has been enabled, Bank
2 HO2S 1 average transition time between 300 mV
and 600 mV is too slow. The lean-to-rich average
transition response time was longer than 94
milliseconds or the rich-to-lean average transition
response time was longer than 105 milliseconds.
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 set as Freeze Frame and in the Failure
Records data.

ªOpen loopº fuel control will be in effect.
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 P0153 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0153 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.

6E±201
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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
Bank 2 HO2S 1 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.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is currently present.
3. HO2S transition time, ratio mean volts and switching
DTCs set for multiple sensors indicate probable
contamination. Before replacing the sensors,
isolate and correct the source of the contamination
to avoid damaging the replacement sensors.