Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 342

6E–398

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code(DTC)

P1120-TPS 1 Throttle Position Sensor (TPS1) Output Abnormal

D06RY00111

Circuit Description

D

The throttle position (TP) sensor circuit provides a
voltage signal relative to throttle blade angle.
The TPS1 voltage will vary about 8% (0.4V) to about
92% (4.6V) at Wide Open Throttle (WOT) in the
specified voltage (about 5V).

This code detects a continuous short to ground or
high in either the circuit or the sensor.

Conditions for setting the DTC

D

The Ignition is “ON”.

D

The TPS1 output is more than 93.6 milliseconds, less
than 2.5% or more than 97.5% in the specified voltage
(5V).

Action Taken When the DTC Sets

D

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

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 P1120 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

D

DTC P1120 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.

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

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
TPS 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 P1120 cannot be duplicated, the information
included in the Failure Records data can be useful in
determined vehicle mileage since the DTC was last
set.

6E–399

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

If it is determined that the DTC occurs intermittently,
performing the DTC P1120 Diagnostic Chart may
isolate the cause of the fault.

Diagnostic Trouble Code(DTC)P1120-TPS 1 Output Abnormal

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to

 Step 2

Go to

 OBD

System

Check

2

1. Ignition “ON”, engine not running.
2. Observe the MAP reading on the Tech 2.

Is the MAP reading less than the specified value?

65kPa

Go to

 Step 3

Go to

 Step 6

3

1. Disconnect the MAP sensor.
2. Connect a test 5 volt reference circuit and the MAP

signal at the MAP sensor harness connector.

3. Observe the MAP reading on the Tech 2.

Is the MAP reading less than the specified value? (If no,
start with diagnosis chart for other sensors in the circuit
and see if 5V returns.)

—

Go to

 Step 5

Go to

 Step 4

4

1. Check the MAP signal circuit between the PCM and

MAP ground circuit.

2. If the MAP signal circuit is open or shorted, repair it

as necessary.

Was the MAP signal circuit open or shorted?

—

Verify repair

Go to 

Step 12

5

Replace the MAP sensor.

Is the action complete?

—

Verify repair

—

6

Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.

Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open throttle
value?

Throttle

Closed TPS1

8–10 % TPS2

8–10 % Wide

Open Throttle

TPS1 90–92

% TPS2

90–92 %

Refer to

Diagnostic

Aids

Go to

 Step 7

7

1. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.

Is the TP sensor reading near the specified value?

0V

Go to

 Step 8

Go to

 Step 9

8

1. Connect a test light between the 5Volt reference

circuit and the TP sensor signal circuit at the TP
sensor harness connector.

2. Observe the TP sensor reading on the Tech 2.

Is the TP sensor reading near the specified value?

5V

Go to

 Step 11

Go to

 Step 10

9

Check the following items;

1. TP1 signal circuit for a short to voltage.
2. TP1 sensor ground circuit for high resistance

between the PCM and the TP sensor.

3. TP1 sensor ground circuit for a poor connection.
4. If a problem is found, repair wiring harness as

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 12

6E–400

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code(DTC)P1120-TPS 1 Output Abnormal

  (Cont'd)

Step

No

Yes

Value(s)

Action

10

Check the following items;

1. TP signal circuit or 5 volt reference circuit for a poor

connection.

2. TP signal circuit or 5 volt reference circuit for high

resistance between the PCM and the TP sensor.

3. If a problem is found, repair wiring harness as

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 12

11

Replace the TP sensor.

Is the action complete?

—

Verify repair

—

12

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed.

Refer to 

ON-Vehicle Service in Power 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?

—

Verify repair

—

6E–401

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) 

P1125  ETC (Electric Throttle Control) Limit Performance Mode

060R200064

Circuit Description

D

The accelerator position (AP1) sensor circuit provides
a voltage signal relative to accelerator pedal angle.
The accelerator pedal angle will vary about 13 % at
idle position to about 87 % at wide open throttle
(WOT).

This code detects if the system is in Limit
Performance Mode (Fail safe Mode) and Multiple
DTCs performance Mode.

Conditions for setting the DTC

D

The Ignition is “ ON”.

D

Limit Performance Mode is active. (Fail safe Mode)

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.

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 P1125 will clear after 40 consecutive trip
cycle during which the warm up cycles have occurred
without a fault.

D

DTC P1125 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

Mis routed harness.