Camshaft Position (CMP) Sensor G40 , checking

Special tools, testers and auxiliary items required 

• Multimeter.
• Wiring diagram.

Test requirements 

• The Motronic 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. Refer to → Motronic Engine Control Module (ECM) J220 , replacing 

Start diagnosis 

• Remove the engine cover with air filter.

• Disconnect the Camshaft Position (CMP) Sensor G40 electrical harness connector - arrow  -.
• Switch the ignition on.

• Using a Multimeter , Check the Camshaft Position (CMP) Sensor G40 electrical harness connector terminals 1 to 3 for voltage.

Specified value: about 4.5 V

• 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 Adapter F/VAG1598 (68 Pin) VAG1598/22. Refer to 24 MULTIPORT FUEL INJECTION (MFI) .

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

• Remove the Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220 , replacing  .

• Using a Multimeter , Check the Camshaft Position (CMP) Sensor G40 electrical harness connector to the Motronic Engine Control Module (ECM) electrical harness connector T80 for an open circuit.

Camshaft Position (CMP) Sensor G40 electrical harness connector terminals	Motronic Engine Control Module (ECM) electrical harness connector T80 terminals or test box sockets
1	62
2	76
3	67

Specified value: 1.5 Ω 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, loose 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. Refer to 28 - Ignition/Glow plug System  .
• Install the engine cover with air filter.
• Erase the DTC memory. Refer to → Diagnostic Mode 04: Reset/delete diagnostic data 
• Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to → 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 Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220 , replacing  .
• Assembly is performed in the reverse of the removal.

Final procedures 

After the 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.

End of diagnosis