Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 776

6E–128

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0101 MAF System Performance

D06R200047

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 or 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 3 to 7g/s at idle. DTC P0101 will
be set if the signal from the MAF sensor does not match a
predicted value based on throttle position and engine
RPM.

Conditions for setting the DTC

D

The engine is running.

D

No TP sensor and MAP sensor DTCs are set.

D

No MAF frequency DTCs are set.

D

System voltage is between 11.5 volts and 16 volts.

Action Taken When the DTC Sets

D

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

D

The PCM calculates an air flow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.

D

The PCM will store condition which were present when
the DTC was set as Freeze Frame and in the Failure
Records data.

Conditions for Clearing the MIL/DTC

D

The PCM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

D

A history DTC P0101 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

D

DTC P0101 can be cleared using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

An intermittent may be caused by the following:

D

Poor connections.

D

Misrouted harness.

D

Rubbed through wire insulation.

D

Broken wire inside the insulation.

D

The duct work at the MAF sensor for leaks.

D

An engine vacuum leak.

D

The PCV system for vacuum leaks.

D

An incorrect PCV valve.

D

The engine oil dip stick not fully seated.

D

The engine oil fill cap loose or missing.

Check for the following conditions:

D

Poor connection at PCM-Inspect harness connectors
for backed out terminals, improper mating, broken

6E–129

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

D

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.

D

Plugged intake air duct or filter element

D

A wide–open throttle acceleration from a stop should
cause the mass air flow displayed on a Tech 2 to
increase 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

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “OFF”.
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 “ON”, Engine“OFF”.

Did the test lamp illuminate?

—

Go to 

Step 6

Go to 

Step 3

3

1. Ignition “ON”, Engine “OFF”.
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 5

Go to

 Step 4

4

1. Ignition “OFF”.
2. Check the 12 volt signal circuit for the following

conditions:

D

An open circuit

D

A short to ground

Was the problem found?

—

Verify repair

—

5

Check the MAF ground circuit for the following
conditions:

D

An open circuit

D

A short to voltage

Was a problem found?

—

Verify repair

—

6

1. Ignition “OFF”.
2. Check the MAF Sensor signal circuit between the

PCM and the MAF Sensor for the following
conditions:

D

An open circuit

D

A short to ground

D

A short to battery voltage

Was a problem found?

—

Verify repair

Go to 

Step 7

6E–130

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0101 – MAF System Performance

  (Cont'd)

Step

No

Yes

Value(s)

Action

7

1. 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)?

3 to 7 g/s

Go to 

Step 8

Go to 

Step 9

8

1. Ignition “OFF”.
2. Disconnect the MAF sensor connector.
3. Ignition “ON”, engine idling.
4. Using a Tech 2, monitor “MAF Frequency”.

Does the Tech 2 indication a “MAF Frequency” at the
specified value?

0 g/s

Go to 

Step 10

Go to 

Step 9

9

Replace the MAF Sensor.

Is the action complete?

—

Verify repair

—

10

Replace 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?

—

Verify repair

—

6E–131

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) 

P0102 MAF Sensor Circuit  Low Frequency

D06R200047

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 3 to 7g/s at idle.  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

D

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

D

System voltage is above 11.5 volts.

D

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

D

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

D

The PCM calculates an air flow value based on idle air
control valve position, throttle position, RPM and
barometric pressure.

D

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

D

The PCM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

D

A history DTC P0102 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P0102 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

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.

D

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

D

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.

D

Plugged intake air duct or filter element – A wide-open
throttle acceleration from a stop should cause the