Opel Frontera UBS. Manual - part 498

6E–122

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0342 (Flash DTC 41) 

CMP (Cam Position) Sensor No Signal

060RW133

Circuit Description

The CMP signal produced by the camshaft position
(CMP) sensor pulses when the engine is running and
crankshaft position (CKP) synchro pulses are also being
received.  The hall type CMP sensor and the CKP sensor
share 5 V and ground connections at the Engine Control
Module ECM.  The third wire at the sensor is a signal
circuit to the ECM.  The ECM uses the CMP signal pulses
to initiate sequential fuel injection.  If the ECM does not
receive pulses on the CMP reference circuit, DTC P0342
will set.

Action Taken When the DTC Sets

D

The ECM 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

DTC P0342 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the ECM battery
feed.

Diagnostic Aids

An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation.  Check for:

D

Poor connection – Inspect the ECM harness and
connectors for 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, disconnect
the ECM, turn the ignition on and observe a voltmeter
connected to the CMP signal circuit at the ECM
harness connector while moving connectors and
wiring harnesses related to the ICM and the CMP
sensor.  A change in voltage will indicate the location
of the fault.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Ensures that the fault is present.

14.Determines whether the fault is being caused by a

missing camshaft magnet or a faulty ECM.  The
voltage measured in this step should read around 4
volts, toggling to near 0 volts when the CMP sensor
interfaces with the camshaft magnet.

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4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0342 —CMP Sensor No Signal

 

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.”
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 “Specific DTC” information

for DTC P0342 until the DTC P0342 test runs.

5. Note test result.

Does the Tech 2 indicate DTC P0342 failed this
ignition?

—

Go to 

Step 3

Refer to

Diagnostic

Aids

3

1. Ignition “ON.”
2. Disconnect the CMP sensor.
3. Measure the voltage between the sensor feed

circuit and the sensor ground circuit at the CMP
sensor harness connector.

Does the voltage measure near the specified value?

4-6 V

Go to 

Step 7

Go to 

Step 4

4

1. Ignition “OFF,” disconnect the ECM and the CMP

sensor.

2. Check for poor connections at the camshaft

position sensor.

3. If a problem is found, repair it as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 5

5

1. Check for poor connections at the ECM.
2. If a problem is found, repair it as necessary.

Was a problem found?

—

Verify repair 

Go to 

Step 6

6

1. Check the following circuits between the ECM and

the CMP sensor:

D

The sensor feed circuit.  Open or short to
ground?

D

The sensor ground circuit.  Open or short to
voltage?

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

—

7

1. Ignition “ON,” engine “OFF.”
2. Measure the voltage between the CMP sensor

signal circuit and the sensor ground circuit at the
CMP sensor harness connector.

Does the voltage measure near the specified value?

4-6 V

Go to 

Step 8

Go to 

Step 9

6E–124

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0342 —CMP Sensor No Signal

  (Cont'd)

Step

No

Yes

Value(s)

Action

8

1. Turn the ignition “OFF.”
2. Disconnect the ECM and connect a DVM to monitor

voltage on the camshaft position signal circuit at the
ECM connector.

3. Ignition “ON.”
4. Monitor the voltage display on the DVM while

repeatedly touching the CMP sensor signal circuit
at the CMP sensor connector with a test light to
ground.

Does the DVM voltage display switch between 0 and
approximately 5 volts when the test light is touched to
the CMP sensor signal circuit?

—

Go to 

Step 12

Go to 

Step 9

9

1. Ignition “OFF.”
2. Leave the ECM disconnected.
3. Ignition “ON.”
4. Probe the camshaft position signal circuit at the

ECM connector with a test light to B+.

5. If the test light is “ON,” locate and repair the short to

ground in the camshaft position input signal circuit.

Was either circuit shorted to ground?

—

Verify repair

Go to 

Step 10

10

1. Ignition “OFF.”
2. Leave the ECM disconnected.
3. Ignition “ON.”
4. Probe the camshaft position signal circuit with a test

light to ground.

5. If the test light is “ON,” locate and repair the short to

voltage in the camshaft position input signal circuit.

Was the test light “ON”?

—

Verify repair

Go to 

Step 11

11

1. Ignition “OFF,” disconnect the ECM (leave the CMP

sensor disconnected).

2. Ignition “ON,” check the following circuit:

D

The CMP sensor signal circuit for an open.

3. If a problem is found, repair it as necessary.

Was a problem found?

—

Verify repair

—

12

1. Ignition “ON.”
2. Remove the CMP sensor from the engine front

cover (leave the sensor wiring connected).

3. Place a magnet on the CMP sensor.  If you use a

magnet that is too small to cover the face of the
sensor, test on every part of the sensor face
because only a small area will respond to this test.

Does the DVM display a voltage near the specified
value?

0 V

Go to 

Step 14

Go to 

Step 13

13

Replace the camshaft position sensor.

Is the action complete?

—

Verify repair

—

14

1. Reinstall the CMP sensor to the engine front cover.
2. Observe the DVM connected to monitor voltage on

the camshaft position signal circuit while cranking
the engine.

Does the voltage toggle between the specified values?

4-0 V

Go to 

Step 15

Go to 

Step 16

6E–125

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0342 —CMP Sensor No Signal

  (Cont'd)

Step

No

Yes

Value(s)

Action

15

Replace the ECM (Refer to the Data Programming in
Case of ECM change).

Is the action complete?

—

Verify repair

—

16

Replace faulty or missing camshaft magnet.

Is the action complete?

—

Verify repair

—