2002 ISUZU AXIOM change time

6E±391
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1112 IAT Sensor Circuit Intermittent Low 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
becomes lower, causing the PCM to monitor a lower
voltage. DTC P1112 will set when the PCM intermittently
detects an excessively low signal voltage on the intake air
temperature sensor signal circuit.
Conditions for Setting the DTC

The engine has been running for over 15 seconds.

Vehicle speed is greater than 48 km/h (30 mph).

IAT signal voltage is greater than 148
C (298
F)
(about 0.10 volt) for a total of 2.5 seconds over a
25-second period of time.
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.

The PCM will substitute a default value for intake air
temperature.
Conditions for Clearing the MIL/DTC

A history DTC P1112 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1112 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±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

6E±404
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1133 HO2S Insufficient Switching Bank 1 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) monitors the
heated oxygen sensor (HO2S) activity for 90 seconds
after ªclosed loopº and stoichiometric operation have
been enabled. During this test period the PCM counts the
number of times that the HO2S signal voltage crosses the
rich-to-lean and lean-to-rich threshold. If the PCM
determines that the HO2S did not switch enough times,
DTC P1133 will be set.
A lean-to-rich switch is determined when the HO2S
voltage changes above and below 450 mV.
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 for accurate exhaust oxygen
content readings further from the engine.
Conditions for Setting the DTC

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

Engine is operating in ªclosed loopº.

The engine has been running at least one minute.

Canister purge duty cycle is greater than 2%.

Engine speed is between 1500 RPM and 3000 RPM.
Mass air flow (MAF) is between 9 g/second and 42
g/second.

Above conditions are present for 3 seconds.

90 seconds after ªclosed loopº and stoichiometric
operation have been achieved, the PCM monitors the
oxygen sensor as it switches above and below 450 mV.
If fewer than 23 rich-to-lean and lean-to-rich switches
are detected, DTC P1133 will be set.
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.

ºOpen loopº fuel control will be in effect.

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 P1133 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1133 can be cleared by using Tech 2 ªClear Infoº
function or by disconnecting the PCM battery feed.

6E±408
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1134 HO2S Transition Time Ratio Bank 1 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) monitors the
heated oxygen sensor (HO2S) activity for 90 seconds
after ªclosed loopº and stoichiometric operation have
been established. During the monitoring period the PCM
counts the number of times that the HO2S responds from
rich-to-lean and from lean-to-rich and adds the amount of
time it took to complete all transitions. With this
information, an average time for all transitions can be
determined. The PCM then divides the rich-to-lean
average by the lean-to-rich average to obtain a ratio. If
the HO2S transition time ratio is not within this range,
DTC P1134 will be set, indicating that the oxygen sensor
is not responding as expected to changes in exhaust
oxygen content.
Conditions for Setting the DTC

No related DTCs.

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

Engine is operating in ªclosed loopº,

The engine has been running at least one minute.

Canister purge duty cycle is greater than 2%.

Engine speed is between 1500 RPM and 3000 RPM.

Mass air flow (MAF) is between 18 g/second and 42
g/second.

Above conditions are present for a 3-second
monitoring period.
90 seconds after ªclosed loopº and stoichiometric
operation have been enabled, Bank 1 HO2S 1
transition ratio between lean-to-rich and rich-to-lean is
less than 0.44 or greater than 3.8.
Action Taken When the DTC Sets

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

ºOpen loopº fuel control will be in effect.

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 P1134 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1134 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
A malfunction in the HO2S heater ignition feed or ground
circuit may cause a DTC P1134 to set. Check HO2S
heater circuitry for intermittent faults or poor connections.
If connections and wiring are OK and DTC P1134
continues to set, replace the Bank 1 HO2S 1.

6E±412
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1153 HO2S Insufficient Switching Bank 2 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) monitors the
heated oxygen sensor (HO2S) activity for 90 seconds
after ªclosed loopº and stoichiometric operation have
been enabled. During this test period the PCM counts the
number of times that the HO2S signal voltage crosses the
rich-to-lean and lean-to-rich thresholds. If the PCM
determines that the HO2S did not switch enough times,
DTC P1153 will be set.
A lean-to-rich switch is determined when the HO2S
voltage changes above and below 450 mV.
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 for accurate exhaust oxygen
content readings further from the engine.
Conditions for Setting the DTC

The engine is operating in ªclosed loopº,

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

The engine has been running for over 60 seconds.

Canister purge duty cycle is greater than 2%.

Engine speed is between 1500 RPM and 3000 RPM.
Mass air flow is between 8 g/second and 42 g/second.

Above conditions are present for a 3 seconds.

90 seconds after ªclosed loopº and stoichiometric
operation have been enabled, the PCM monitors the
oxygen sensor switching above and below 450 mV. If
fewer than 27 rich-to-lean and lean-to-rich switches for
Bank 2 HO2S 1 are detected, DTC P1153 will set.
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.

ºOpen loopº fuel control will be in effect.

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 P1153 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1153 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.

6E±416
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1154 HO2S Circuit Transition Time Ratio Bank 2 Sensor 1
060R200054
Circuit Description
The powertrain control module (PCM) monitors the
heated oxygen sensor (HO2S) activity for 90 seconds
after ªclosed loopº and stoichiometric operation have
been enabled. During the monitor period the PCM counts
the number of times that the HO2S responds from
rich-to-lean and from lean-to-rich and adds the amount of
time it took to complete all transitions. With this
information, an average time for all transitions can be
determined. The PCM then divides the rich-to-lean
average by the lean-to-rich average to obtain a ratio. If
the HO2S transition time ratio is not within this range,
DTC P1154 will be set, indicating that the oxygen sensor
is not responding as expected to changes in exhaust
oxygen content.
Conditions for Setting the DTC

No related DTCs.

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

The engine is operating in ªclosed loopº,

The engine has been running at least one minute.

Canister purge duty cycle is greater than 2%.

Engine speed is between 1500 RPM and 3000 RPM.

Mass air flow is between 18 g/second and 42 g/second.

Above conditions are present for a 3-second
monitoring period.
90 seconds after ªclosed loopº and stoichiometric
operation have been enabled, Bank 2 HO2S 1
transition ratio between lean to rich and rich to lean is
less than 0.44 or greater than 3.8.
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.

ºOpen loopº fuel control will be in effect.

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 P1154 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P1154 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
A multifunction in the HO2S heater ignition feed or ground
circuit may cause a DTC P1154 to set. Check HO2S
heater circuitry for intermittent faults or poor connections.

6E±448
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1290 ETC Forced Idle Mode
060R200069
Circuit Description

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal angle (AP1) will vary from
about 13 % at idle position to about 87 % at wide
open throttle (WOT).
This code detects that if the system is in Forced Idle
Mode. (Fail safe Mode)
Conditions for setting the DTC

The Ignition is ªONº.

Forced Idle Mode is active. (Fail safe Mode)
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 P1290 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1290 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Mis routed harness.

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 P1290 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,
performing the DTC
P1290 Diagnostic Chart may isolate the cause of the
fault.