Camshaft Position Sensor: Testing and Inspection

Camshaft Position Sensors, Checking

The following procedure is used to diagnose both Camshaft Position (CMP) Sensor G40 and Camshaft Position (CMP) Sensor 2 G163

Note: Use only gold-plated terminals when servicing terminals in harness connectors of Camshaft Position (CMP) Sensor G40 and Camshaft Position (CMP) Sensor 2 G163.

Special tools, testers and auxiliary items required
- Multimeter.
- Wiring diagram.

Test requirements
- The Engine Control Module (ECM) J220 fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N" .
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.

Test procedure
- Perform a preliminary check to verify the customers complaint.

Start diagnosis




- Disconnect the Camshaft Position (CMP) Sensor G40 electrical harness connector -A arrow- or Camshaft Position (CMP) Sensor 2 G163 -B arrow-
- Switch the ignition on.





- Using a Multimeter, Check the Camshaft Position (CMP) Sensor electrical harness connector terminals 1 to 3 for voltage.
Specified value: about 5.0V

- Switch the ignition off.

If the specification was not obtained:

Checking wiring

If the manufacturers test box is being used. Perform the following step.

- Install the Test Box 105 Pin VAG1598/31 (Engine Code ATQ ) Test Box 80 Pin VAG1598/22 (Engine Code AHA).

If the manufacturers test box is not being used. Perform the following step.

- Remove the Engine Control Module (ECM) J220.




Using a Multimeter, Check the Camshaft Position (CMP) Sensor G40 or Camshaft Position (CMP) Sensor 2 G163 electrical harness connector to the Engine Control Module (ECM) J220 electrical harness connector for an open circuit.

(Engine Code ATQ)





(Engine Code AHA)




Specified value: 1.5 ohms Max.

If the specified value was not obtained:

- Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).
- Check the wiring connection for damage, corrosion, lose or broken terminals.
- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring and voltage supply was OK:

- Replace the Camshaft Position (CMP) Sensor G40 or Camshaft Position (CMP) Sensor 2 G163 .

If no malfunction is found in the wiring and voltage supply was not OK:

- Erase the DTC memory.
- Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code.

- End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:
- Replace the Engine Control Module (ECM) J220.
- Assembly is performed in the reverse of the removal.

Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.