Camshaft Position (CMP) Sensors , Checking

This procedure is used to check Camshaft Position (CMP) Sensors G40, G300, G163, G301.

Special tools, testers and auxiliary items required 

• Multimeter.
• Wiring diagram.

Test requirements 

• The 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.

Test procedure 

• Perform a preliminary check to verify the customers complaint. Refer to → General Diagnosis .

Start diagnosis 

Checking activation

Fig 1: Identifying Front Engine Cover

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• Remove the front engine cover - arrows  -.

Fig 2: Removing/Installing Rear Engine Cover

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• Remove the rear engine cover - arrows  -.
• Disconnect the electrical harness connector of the Camshaft Position (CMP) Sensor G40 to be tested.
• Switch the ignition on.

Fig 3: Checking Camshaft Position Sensor G40 Electrical Harness Connector Terminals 1 To 3 For Voltage

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• Using a Multimeter , Check the Camshaft Position (CMP) Sensor 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 → 24 - FUEL INJECTION SYSTEM .

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

• Remove the Engine Control Module (ECM) J623. Refer to → Engine Control Module (ECM) J623 , Removing and Installing .

Fig 4: Identifying 3-Pin Electrical Harness Connector & Terminals

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• Using a Multimeter , Check the Camshaft Position (CMP) Sensor electrical harness connector to the Engine Control Module (ECM) J623 electrical harness connector T60 for an open circuit.

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 G40 → 15 - ENGINE - CYLINDER HEAD, VALVETRAIN .

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

• Replace the Engine Control Module (ECM) J623. Refer to → Engine Control Module (ECM) J623 , Removing and Installing .

Assembly is performed in the reverse order of removal, note the following:

Final procedures 

After repair work, the following work steps must be performed in the mentioned sequence:

1. Check the DTC memory.
2. If necessary, erase the DTC memory. Refer to Diagnostic Mode 04: Reset/delete Diagnostic Data .
3. If the DTC memory was erased, generate readiness code. Refer to Readiness Code .

• End diagnosis and switch ignition off.