sensor ISUZU AXIOM 2002 Service Repair Manual

6E±132
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

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
Mass Air Flow (MAF) display on the Tech 2 while
moving connectors and wiring harnesses related to the
sensor.

Plugged intake air duct or filter element

A wide±open throttle acceleration from a stop should
cause the mass air flow displayed on a Tech 2 toincrease from about 3±6 g/s at idle to 100 g/s or greater
at the time of the 1±2 shift. If not, check for a restriction.
A change in the display will indicate the location of
the fault.
If DTC P0101 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 P001 Diagnostic Chart may
isolate the cause of the fault.
DTC P0101 ± MAF System Performance

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªOFFº.
2. Disconnect the Mass Air Flow (MAF) Sensor
harness connector from the MAF Sensor.
3. Place an unpowered test lamp between the 12 volt
signal circuit and the ground circuit, both at the MAF
Sensor connector.
4. Ignition ªONº, EngineªOFFº.
Did the test lamp illuminate?
ÐGo to Step 6Go to Step 3
31. Ignition ªONº, Engine ªOFFº.
2. Using a Digital Voltmeter (DVM), check the 12 volt
signal circuit for the correct voltage.
Did the DVM indicate a value within the following
range?
11.5 to 12.5
Volt
Go to Step 5Go to Step 4
41. Ignition ªOFFº.
2. Check the 12 volt signal circuit for the following
conditions:

An open circuit

A short to ground
Was the problem found?
ÐVerify repairÐ
5Check the MAF ground circuit for the following
conditions:

An open circuit

A short to voltage
Was a problem found?
ÐVerify repairÐ
61. Ignition ªOFFº.
2. Check the MAF Sensor signal circuit between the
PCM and the MAF Sensor for the following
conditions:

An open circuit

A short to ground

A short to battery voltage
Was a problem found?
ÐVerify repairGo to Step 7

6E±133
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0101 ± MAF System Performance

 
StepNo Ye s Value(s) Action
71. Connect the MAF Sensor wiring harness connector
to the MAF Sensor.
2. Connect the Tech 2 to the vehicle.
3. Place the Transmission in Park/Neutral, and fully
apply the Parking Brake.
4. Start the engine.
5. Select the Mass Air Flow (MAF) parameter on the
Tech 2.
With the engine idling, does the Tech 2 display the
following value(s)?
4 to 7 g/sGo to Step 8Go to Step 9
8Observe the Tech 2 value while increasing the engine
RPM to its upper limit.
Does the Tech 2 display the following value(s)?
25 to 40 g/sGo to Step 10Go to Step 9
9Replace the MAF Sensor.
Is the action complete?
ÐVerify repairÐ
10Replace the PCM.
IMPORTANT:The PCM must be reprogrammed. Refer
to PCM reprogramming.
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±134
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0102 MAF Sensor Circuit Low Frequency
060R200052
Circuit Description
The mass air flow (MAF) sensor measures the amount of
air which passes through it into the engine during a given
time. The powertrain control module (PCM) uses the
mass air flow information to monitor engine operating
conditions for fuel delivery calculations. A large quantity
of air entering the engine indicates an acceleration or high
load situation, while a small quantity of air indicates
deceleration or idle.
The MAF sensor produces a frequency signal which can
be monitored using a Tech 2. The frequency will vary
within a range of around 4 to 7g/s at idle to around 25 to 40
g/s at maximum engine load. DTC P0102 will be set if the
signal from the MAF sensor is below the possible range of
a normally operating MAF sensor.
Conditions for Setting the DTC

The engine is running above 500 RPM for more than
10 seconds.

System voltage is above 11.5 volts.

MAF signal frequency is below 1.6g/s for a total of
50-percent of the last 1000 samples monitored. A
sample is taken every cylinder event.
Action Taken When the DTC Sets

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

The PCM calculates an air flow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.
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 P0102 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0102 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.

Misrouted harness ± Inspect the MAF sensor harness
to ensure that it is not routed too close to high voltage
wires.

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
Tech 2 while moving connectors and wiring harnesses
related to the MAF sensor. A change in the display will
indicate the location of the fault.

Plugged intake air duct or filter element ± A wide-open
throttle acceleration from a stop should cause the
mass air flow displayed on a Tech 2 to increase from

6E±135
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
about 3-6 g/second at idle to 100 g/second or greater
at the time of the 1-2 shift. If not, check for a restriction.
If DTC P0102 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.2. This step verifies that the problem is present at idle.
4. A voltage reading of less than 4 or over 5 volts at the
MAF sensor signal circuit indicates a fault in the
wiring or a poor connection.
5. This verifies that ignition feed voltage and a good
ground are available at the MAF sensor.
DTC P0102 ± MAF Sensor Circuit Low Frequency

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Start the engine.
2. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
Is the ªMAF Frequencyº below the specified value?
1.6 g/sGo to Step 3Go to Step 5
31. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ªDTCº info for DTC P0102.
Does the Tech 2 indicate DTC P0102 failed this
ignition?
ÐGo to Step 4
Refer to
Diagnostic
Aids
41. Ignition ªOFFº.
2. Disconnect the MAF sensor connector.
3. Ignition ªONº, engine ªOFFº.
4. Using a DVM, measure voltage between the MAF
sensor signal circuit and battery ground.
Is the voltage near the specified value?
11.5±12 VGo to Step 5Go to Step 8
5Connect a test light between the MAF sensor ignition
feed and ground circuits at the MAF sensor harness
connector.
Is the test light ªONº?
ÐGo to Step 7Go to Step 6
6Connect a test light between the MAF sensor ignition
feed circuit and battery ground.
Is the test light ªONº?
ÐGo to Step 11Go to Step 7
71. Check for a poor connection at the MAF sensor.
2. If a poor connection is found, replace the faulty
terminal(s).
Was a poor connection found?
ÐVerify repairGo to Step 12
81. Ignition ªOFFº.
2. Disconnect the MAF sensor.
3. Disconnect the PCM connector for the MAF signal
circuit.
4. Ignition ªONº, engine ªOFFº.
5. With the DVM, measure the voltage between the
MAF signal terminal at the PCM and battery ground.
Is the voltage under the specified value?
0 VGo to Step 9Go to Step 10

6E±136
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0102 ± MAF Sensor Circuit Low Frequency

 
StepNo Ye s Value(s) Action
91. Ignition ªOFFº.
2. Disconnect the PCM connector.
3. Ignition ªONº.
4. Check the MAF sensor signal circuit for a short to 5
volts.
Is the action complete?
ÐVerify repairÐ
101. Ignition ªOFFº.
2. Disconnect the PCM connector.
3. Ignition ªONº.
4. Check the MAF sensor signal circuit between the
PCM and the MAF sensor for an open, short to
ground, or short to the MAF ground circuit.
Is the action complete?
ÐVerify repairGo to Step 13
11Locate and repair the open in the ground circuit to the
MAF sensor.
Is the action complete?
ÐVerify repairÐ
12Locate and repair the open in the ignition feed circuit to
the MAF sensor.
Is the action complete?
ÐVerify repairÐ
13Replace the MAF sensor.
Is the action complete?
ÐVerify repairGo to Step 14
14Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain 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±137
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0103 MAF Sensor Circuit High Frequency
060R200052
Circuit Description
The mass air flow (MAF) sensor measures the amount of
air which passes through it into the engine during a given
time. The powertrain control module (PCM) uses the
mass air flow information to monitor engine operating
conditions for fuel delivery calculations. A large quantity
of air entering the engine indicates an acceleration or high
load situation, while a small quantity of air indicates
deceleration or idle.
The MAF sensor produces a frequency signal which can
be monitored using a Tech 2. The frequency will vary
within a range of around 4 to 7g/s at idle to around 25 to 40
g/s at maximum engine load. DTC P0103 will be set if the
signal from the MAF sensor is above the possible range of
a normally operating MAF sensor.
Conditions for Setting the DTC

The engine is running above 500 RPM for more than
10 seconds.

System voltage is above 11.5 volts.

MAF signal frequency is above 40g/s for a total of 50
percent of the last 200 samples monitored. A sample
is taken every cylinder event.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.
The PCM calculates an airflow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.

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 P0103 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0103 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
If DTC P0103 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. This step verifies that the problem is present at idle.

6E±138
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
4. A frequency reading with the MAF sensor connector
disconnected indicates an electromagnetic
interference (EMI) related fault.
8. This vehicle is equipped with a PCM which utilizes
an electrically erasable programmable read only
memory (EEPROM). When the PCM is being
replaced, the new PCM must be programmed.
Refer to
PCM Replacement and Programming
Procedures
in Powertrain Control Module (PCM)
and Sensors
.

6E±139
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0103 ± MAF Sensor Circuit High Frequency

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ªDTCº info for DTC P0103.
Does the Tech 2 indicate DTC P0103 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Start the engine.
2. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
Is ªMAF Frequencyº above the specified value?
40g/sGo to Step 4Go to Step 7
41. Ignition ªOFFº.
2. Disconnect the MAF sensor connector.
3. Ignition ªONº, engine idling.
4. Using a Tech 2, monitor ªMAF Frequencyº.
Does the Tech 2 indicate a ªMAF Frequencyº at the
specified value?
0g/sGo to Step 5Go to Step 6
5Replace the MAF sensor.
Is the action complete?
ÐVerify repairGo to Step 8
61. Check the MAF harness for incorrect routing near
high voltage components (solenoids, relays,
motors).
2. If incorrect routing is found, correct the harness
routing.
Was a problem found?
ÐVerify repairGo to Step 7
71. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
2. Quickly snap open throttle to wide open throttle
while under a road load and record value.
Does the Tech 2 indicate ªMAF Frequencyº above the
specified value?
40g/sGo to Step 5Go to Step 8
8Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain 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±140
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0106 MAP System Performance
060R200051
Circuit Description
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum). The
MAP sensor signal voltage to the powertrain control
module (PCM) varies from below 2 volts at idle (high
vacuum) to above 4 volts at wide-open throttle (low
vacuum) at sea level.
The MAP sensor is used to determine manifold pressure
changes while the linear exhaust gas recirculation (EGR)
flow test diagnostic is being run (refer to DTC P0401),
engine vacuum level for some other diagnostics, and
barometric pressure (BARO). The PCM compares the
MAP sensor signal to a calculated MAP based on throttle
position and various engine load factors. If the PCM
detects a MAP signal that varies excessively above or
below the calculated value, DTC P0106 will set.
Conditions for Setting the DTC

No TP sensor DTCs are present.

Engine speed is steady, changing less then 100 RPM.

Engine speed is between 1000 rpm and 4000 rpm.

Throttle position is steady, throttle angle changes less
than 1%.

EGR flow rate is steady, changing less than 4%.

No change in brake switch, A/C clutch, TCC or power
steering pressure switch status.

Above conditions are met for longer than 1 second.

Actual MAP value varies more than 10 kPa.
The MAP value must vary for a total of 10 seconds over
a 20-second period of time that the samples were
monitored.

The failure must occur for 2 consecutive trips.
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 default to a BARO value of 79.3 kPa.

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 P0106 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0106 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.

6E±141
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
MAP 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 P0106 cannot be duplicated, the information
included in the Failure Records data can be useful indetermining vehicle mileage since the DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC P1107 Diagnostic Chart may isolate
the cause of the fault.
DTC P0106 ± MAP System Performance

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ªDTCº info for DTC P0106.
Does the Tech 2 indicate DTC P0106 failed?
ÐGo to Step 4Go to Step 3
31. Check for the following conditions:

Vacuum hoses disconnected, damaged, or
incorrectly routed

Intake manifold vacuum leaks

Vacuum leaks at throttle body

Vacuum leaks at EGR valve flange and pipes

Crankcase ventilation valve faulty, missing or
incorrectly installed.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repair
Refer to
Diagnostic
Aids
41. Disconnect the MAP sensor electrical connector.
2. Observe the MAP value displayed on the Tech 2.
Is the MAP value near the specified value?
11 kPaGo to Step 5Go to Step 13
51. Connect a test light between B+ and the MAP
sensor signal circuit at the MAP sensor harness
connector.
2. Observe the MAP value displayed on the Tech 2.
Is the MAP value near the specified value?
105 kPaGo to Step 6Go to Step 9
61. Jumper the 5 volt reference circuit and the MAP
signal circuit together at the MAP sensor harness
connector.
2. Observe the MAP value displayed on the Tech 2.
Is the MAP value near the specified value?
104 kPaGo to Step 7Go to Step 8
71. Ignition ªOFFº.
2. Disconnect the PCM and check the sensor ground
circuit for high resistance, an open between the
PCM and the MAP sensor, or for a poor connection
at the PCM.
3. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 11