Opel Frontera UE. Manual - part 935

6E2–126

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0121 –TP System Performance

  (Cont'd)

Step

No

Yes

Value(s)

Action

10

Check the following items:

1. TP signal circuit or 5 volt reference “A” circuit for a

poor connection.

2. TP signal circuit or 5 volt reference “A” 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.

Is the action complete?

—

Verify repair

—

6E2–127

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0122 TP Sensor Circuit Low Voltage

D06RW059

Circuit Description

The throttle position (TP) sensor circuit provides a voltage
signal that changes relative to throttle blade angle.  The
signal voltage will vary from below 0.6 volts at closed
throttle to about 4.5 volts at wide open throttle (WOT).
The TP signal is used by the powertrain control module
(PCM) for fuel control and many of the PCM-controlled
outputs.

Conditions for Setting the DTC

D

The ignition is “ON.”

D

TP sensor signal voltage is less than 0.22 volt for a total
of 0.78 second over a 1.5-second period.

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 conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

D

The PCM will use a default throttle position based on
mass air flow and RPM.

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 P0122 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P0122 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

The TP Sensor shares a 5 Volt reference with the EGR
Valve.

If these codes are also set, it could indicate a
problem with the 5 Volt reference circuit or
components itself.

D

The TP Sensor share a ground with the EGR Valve and
the IAT Sensor.

D

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

If DTC P0122 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.

6E2–128

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0122 –TP Sensor Circuit  Low Voltage

 

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 “ON,” engine “OFF.”
2. With the throttle closed, observe the “TP Sensor”

display on the Tech 2.

Is the “TP Sensor” below the specified value?

0.22 V

Go to 

Step 4

Go to 

Step 3

3

1. Ignition “ON,” engine “OFF.”
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 the “DTC” info for DTC

P0122.

Does the Tech 2 indicate DTC P0122 failed?

—

Go to 

Step 4

Refer to

Diagnostic

Aids

4

1. Ignition “OFF.”
2. Disconnect the TP sensor electrical connector.
3. Jumper the 5 volt reference “A” circuit and the TP

signal together at the TP sensor harness connector.

4. Ignition “ON.”
Observe the “TP Sensor” display on the Tech 2.

Is the “TP Sensor” at the specified value?

5 V

Go to 

Step 10

Go to 

Step 5

5

1. Disconnect jumper.
2. Connect a test light between B+ and the TP sensor

signal circuit at the TP sensor harness connector.

Observe the “TP Sensor” display on the Tech 2.

Is the “TP Sensor” at the specified value? (If no, start
with diagnosis chart for other sensors in the circuit and
see if 5V returns.)

5 V

Go to 

Step 6

Go to 

Step 8

6

1. Ignition “OFF.”
2. Disconnect the PCM and check the 5 volt reference

“A” circuit for an open or short to ground.

3. If the 5 volt reference “A” circuit is open or shorted to

ground, repair it as necessary.

Was the 5 volt reference “A” circuit open or shorted to
ground?

—

Verify repair

Go to 

Step 7

7

Check the 5 volt reference “A” circuit for a poor
connection at the PCM and replace the terminal if
necessary.

Did the terminal require replacement?

—

Verify repair

Go to 

Step 12

8

1. Ignition “OFF.”
2. Disconnect the PCM, and check the TP signal

circuit for an open, short to ground, or short to the
sensor ground circuit.

3. If the TP sensor signal circuit is open or shorted to

ground, repair it as necessary.

Was the TP signal circuit open or shorted to ground?

—

Verify repair

Go to 

Step 9

6E2–129

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0122 –TP Sensor Circuit  Low Voltage

  (Cont'd)

Step

No

Yes

Value(s)

Action

9

Check the TP sensor signal circuit for a poor
connection at the PCM and replace the terminal if
necessary.

Did the terminal require replacement?

—

Verify repair

Go to 

Step 12

10

Check the TP sensor signal circuit for a poor
connection at the TP sensor and replace the terminal if
necessary.

Did the terminal require replacement?

—

Verify repair

Go to 

Step 11

11

Replace the TP sensor.

Is the action complete?

—

Verify repair

—

12

Replace the PCM.

Is the action complete?

—

Verify repair

—