Camshaft Position Sensor 3

The following procedure is used to diagnose Camshaft Position (CMP) Sensor 3 G300 which is controlled by Motronic Engine Control Module (ECM) J623.

Special tools, testers and auxiliary items required 

• Multimeter.
• Wiring diagram.

Test requirements 

• The Motronic Engine Control Module (ECM) J623 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.

Procedure 

• Disconnect the Camshaft Position (CMP) Sensor 3 G300 electrical harness connector - 4  -.
• Switch the ignition on.

• Using a Multimeter, Check the Camshaft Position (CMP) Sensor 3 G300 electrical harness connector terminals 1 to 3 for voltage.

Specified value: about 5.0 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 test box. Refer to → .

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

• Remove the Motronic Engine Control Module (ECM) J623. Refer to → .

• Using a Multimeter, Check the Camshaft Position (CMP) Sensor 3 G300 electrical harness connector to the Motronic Engine Control Module (ECM) J623 electrical harness connector T60a for an open circuit.

Camshaft Position (CMP) Sensor 3 G300 electrical harness connector terminals	Motronic Engine Control Module (ECM) J623 electrical harness connector T60a terminals or test box sockets
1	37
2	59
3	52

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, 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 3 G300. Refer to → .

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

• Replace the Motronic Engine Control Module (ECM) J623. Refer to → .
• Assembly is performed in the reverse order of 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. Refer to Diagnostic Mode 04 - Erase DTC Memory .
3. If the DTC memory was erased, generate readiness code. Refer to Readiness Code .

• End of diagnosis.