Variable Valve Timing Actuator: Testing and Inspection

Diagnostic Procedures

Camshaft Adjustment Valve, Checking

Camshaft Adjustment Valve 1

The following procedure is used to diagnose Camshaft Adjustment Valve 1 (N205) which is controlled by Motronic Engine Control Module (ECM) (J623).

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (SC8) 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.

Procedure

- Disconnect the Camshaft Adjustment Valve 1 (N205) electrical harness connector - 2 -





Checking internal resistance

- Using a Multimeter, check the Camshaft Adjustment Valve 1 (N205) terminals 1 to 2 for resistance.





Specified value: 5.0 to 8.0 ohms (at approx. 20 °C)

If the specified value was not obtained:

- Replace Camshaft Adjustment Valve 1 (N205).

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 2 to Ground (GND) for voltage.

- Switch the ignition off.

Specified value: battery voltage.

If the specified value was not obtained:

- Check the wiring connection from the Camshaft Adjustment Valve 1 (N205) electrical harness connector terminal 2 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, lose 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.

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

- Remove the Motronic Engine Control Module (ECM) (J623).

- Using a Multimeter, check the Camshaft Adjustment Valve 1 (N205) electrical harness connector terminal 1 to the Motronic Engine Control Module (ECM) (J623) electrical harness connector T60a for an open circuit.









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, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

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

- Replace the Motronic Engine Control Module (ECM) (J623).

- 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. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.

Camshaft Adjustment Valve 1, Exhaust

The following procedure is used to diagnose Camshaft Adjustment Valve 1 (exhaust) (N318) which is controlled by Motronic Engine Control Module (ECM) (J623).

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (SC8) 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.

Procedure

- Disconnect the Camshaft Adjustment Valve 1 (exhaust) (N318) electrical harness connector - 1 -





Checking internal resistance

- Using a Multimeter, check the Camshaft Adjustment Valve 1 (exhaust) (N318) terminals 1 to 2 for resistance.





Specified value: 5.0 to 8.0 ohms (at approx. 20 °C)

If the specified value was not obtained:

- Replace Camshaft Adjustment Valve 1 (exhaust) (N318).

If the specified value was obtained:

Checking voltage

- Switch the ignition on.

- Using a Multimeter, Check the Camshaft Adjustment Valve 1 (exhaust) (N318) electrical harness connector terminal 2 to Ground (GND) for voltage.

- Switch the ignition off.

Specified value: battery voltage.

If the specified value was not obtained:

- Check the wiring connection from the Camshaft Adjustment Valve 1 (exhaust) (N318) electrical harness connector terminal 2 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, lose 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.

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

- Remove the Motronic Engine Control Module (ECM) (J623).

- Using a Multimeter, check the Camshaft Adjustment Valve 1 (exhaust) (N318) electrical harness connector terminal 1 to the Motronic Engine Control Module (ECM) (J623) electrical harness connector T60a for an open circuit.









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, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

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

- Replace the Motronic Engine Control Module (ECM) (J623).

- 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. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.

Camshaft Adjustment Valve 2

The following procedure is used to diagnose Camshaft Adjustment Valve 2 (N208) which is controlled by Engine Control Module (ECM) 2 (J624).

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (SC8) 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.

Procedure

- Disconnect the Camshaft Adjustment Valve 2 (N208) electrical harness connector - 3 -





Checking internal resistance

- Using a Multimeter, check the Camshaft Adjustment Valve 2 (N208) terminals 1 to 2 for resistance.





Specified value: 5.0 to 8.0 ohms (at approx. 20 °C)

If the specified value was not obtained:

- Replace Camshaft Adjustment Valve 2 (N208).

If the specified value was obtained:

Checking voltage

- Switch the ignition on.

- Using a Multimeter, Check the Camshaft Adjustment Valve 2 (N208) electrical harness connector terminal 2 to Ground (GND) for voltage.

- Switch the ignition off.

Specified value: battery voltage.

If the specified value was not obtained:

- Check the wiring connection from the Camshaft Adjustment Valve 2 (N208) electrical harness connector terminal 2 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, lose 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.

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

- Remove the Engine Control Module (ECM) 2 (J624).

- Using a Multimeter, check the Camshaft Adjustment Valve 2 (N208) electrical harness connector terminal 1 to the Engine Control Module (ECM) 2 (J624) electrical harness connector T60d for an open circuit.









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, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

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

- Replace the Engine Control Module (ECM) 2 (J624).

- 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. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.

Camshaft Adjustment Valve 2, Exhaust

The following procedure is used to diagnose Camshaft Adjustment Valve 2 (exhaust) (N319) which is controlled by Engine Control Module (ECM) 2 (J624).

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (SC8) 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.

Procedure

- Disconnect the Camshaft Adjustment Valve 2 (exhaust) (N319) electrical harness connector - 4 -





Checking internal resistance

- Using a Multimeter, check the Camshaft Adjustment Valve 2 (exhaust) (N319) terminals 1 to 2 for resistance.





Specified value: 5.0 to 8.0 ohms (at approx. 20 °C)

If the specified value was not obtained:

- Replace Camshaft Adjustment Valve 2 (exhaust) (N319).

If the specified value was obtained:

Checking voltage

- Switch the ignition on.

- Using a Multimeter, Check the Camshaft Adjustment Valve 2 (exhaust) (N319) electrical harness connector terminal 2 to Ground (GND) for voltage.

- Switch the ignition off.

Specified value: battery voltage.

If the specified value was not obtained:

- Check the wiring connection from the Camshaft Adjustment Valve 2 (exhaust) (N319) electrical harness connector terminal 2 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, lose 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.

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

- Remove the Engine Control Module (ECM) 2 (J624).

- Using a Multimeter, check the Camshaft Adjustment Valve 2 (exhaust) (N319) electrical harness connector terminal 1 to the Engine Control Module (ECM) 2 (J624) electrical harness connector T60d for an open circuit.









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, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

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

- Replace the Engine Control Module (ECM) 2 (J624).

- 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. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.