Camshaft Position Sensor, Checking

Special tools and workshop equipment 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 connections between engine/transmission/chassis OK.
• Ignition switched OFF.

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start diagnosis 

-- Remove the engine cover. Refer to the Repair Information.

-- Disconnect the Camshaft Position Sensor electrical harness connector.

-- 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: near 5.0 V

-- Switch the ignition OFF.

If the specified value was Not obtained:

Checking wiring 

If the manufacturers test box is being used, perform the following step.

-- Install the test box.

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

-- Remove the Motronic Engine Control Module (ECM) -J220-. Refer to the Repair Information.

-- Using a multimeter, Check the Camshaft Position (CMP) Sensor -G40- electrical harness connector to the Motronic Engine Control Module (ECM) electrical harness connector T121 for an open circuit.

Camshaft Position (CMP) Sensor -G40- electrical harness connector terminals	Motronic Engine Control Module (ECM) electrical harness connector T121 terminals or test box sockets
1	98
2	86
3	108

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.

-- 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-.

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

-- Replace the Motronic Engine Control Module (ECM) -J220-. Refer to the Repair Information.

-- Install the engine cover. Refer to the Repair Information.

Final procedures 

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

1. Check the DTC memory DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code READINESS CODE .