engine coolant ISUZU AXIOM 2002 Service Owners Manual

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

6E±396
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

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±406
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1133 ± HO2S Insufficient Switching Bank 1 Sensor 1

 
StepNo Ye s Value(s) Action
11Replace the exhaust pipes, as required.
Is your action complete?
ÐGo to Step 2Ð
12Check for leaks at the exhaust manifold.
Are there leaks at the exhaust manifold?
ÐGo to Step 13Go to Step 14
13Tighten the bolts to specifications or replace the
manifold if necessary.
Is your action complete?
ÐGo to Step 2Ð
14Visually/physically inspect the following items:

Ensure that the Bank 1 HO2S 1 is securely
installed.

Check for corrosion on the terminals.

Check the terminals at Bank 1 HO2S 1 and at the
PCM.

Check for damaged wiring.
Was a problem found in any of the above areas?
ÐVerify repairGo to Step 15
151. Disconnect Bank 1 HO2S 1.
2. Ignition ªONº.
3. Using a DVM at the PCM side of the connector,
check the voltage between the high signal circuit
and ground. Also measure between the low signal
circuit and ground.
Are both voltages in the specified range?
3-4 mVGo to Step 18Go to Step 16
161. Ignition ªOFFº.
2. Check for damage to PCM pins or terminals.
Was a problem found.
ÐVerify repairGo to Step 17
17Check for a short to voltage or ground or an open in the
signal circuit.
Was a problem found?
ÐVerify repairGo to Step 18
181. Ignition ªOFFº.
2. Disconnect the PCM connector.
3. With the HO2S disconnected, check for high and
low signal circuits shorted together between the
PCM and HO2S.
Was a problem found?
ÐVerify repairGo to Step 19
19With the PCM connected and Bank 1 HO2S 1
disconnected from the harness, check Bank 1 HO2S 1
with a Tech 2.
Is the voltage in the specified range?
425-475 mVGo to Step 21Go to Step 22
20Replace the affected heated oxygen sensors.
NOTE: Before replacing the sensors, the cause of the
contamination must be determined and corrected.

Fuel contamination

Use of improper RTV sealant.

Engine oil/coolant consumption.
Is the action complete?
ÐVerify repairÐ

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.