Variable Valve Timing Actuator: Testing and Inspection
Camshaft Adjustment Valve 1, Checking
Special tools, testers and auxiliary items required
• Multimeter.
• Wiring diagram.
Test requirements
• Fuse (S282) fuse OK.
• Motronic Engine Control Module (ECM) Power Supply Relay (J271) 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 ] General Diagnosis.
- Remove engine cover - arrows -.
Start diagnosis
- Disconnect Camshaft Adjustment Valve 1 (N205) electrical harness connector - 1 -.
- Using a Multimeter, check the Camshaft Adjustment Valve 1 (N205) for resistance.
Specified value: 5.0 to 8.0 ohms (at approx. 20° C)
If the specified value was not obtained:
- Replace the Camshaft Adjustment Valve 1 (N205 ). Refer to Fuel Injection and Ignition Repair Information.
If the specified value was obtained:
Checking voltage
- Switch the ignition on.
- Using a Multimeter, Check the Camshaft Adjustment Valve 1 (N205) electrical harness connector terminal 1 to Ground (GND) for voltage.
- Switch the ignition off.
Specified value: battery voltage.
If the specified value was not obtained:
- Check the Camshaft Adjustment Valve 1 (N205) electrical harness connector terminal 1 to the Motronic Engine Control Module (ECM) Power Supply Relay (J271) socket 2/87 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 the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
- Install the test box. Refer to Fuel Injection and Ignition Repair Information
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, Replacing ] Service and Repair.
- Using a Multimeter, Check the Camshaft Adjustment Valve 1 (N205) electrical harness connector terminal 2 to the Engine Control Module (ECM) electrical harness connector T60 terminal 20 for resistance.
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, loose or broken terminals.
- If necessary, repair the faulty wiring connection.
If no malfunction is found in the wiring and voltage supply was OK:
- Erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.
- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.
- End of diagnosis.
If the DTC does return and no malfunction is detected in the wiring and voltage supply was not OK:
- Replace the Engine Control Module (ECM) (J623 ). Refer to => [ Engine Control Module, Replacing ] Service and Repair.
- Assembly is performed in the reverse of the removal.
Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check the DTC memory. => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.
2. If necessary, erase the DTC memory. => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.
3. If the DTC memory was erased, generate readiness code. => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.
End of diagnosis