Cylinder Block Coolant Valve Checking

Cylinder Block Coolant Valve Checking

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• The Cylinder Block Coolant Valve (N545) fuse OK.

• Battery voltage at least 12.5 V.

• All electrical consumers switched off (radiator fan must NOT run during test).

• A/C switched off.

• The ignition switched Off.

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.

Start diagnosis

- Disconnect the Cylinder Block Coolant Valve (N545) electrical harness connector.

Checking internal resistance

- Using a multimeter, check the Cylinder Block Coolant Valve (N545) terminals 1 to 2 for resistance.

Specified value: 30.4 +/- 4ohms

If the specified value was Not obtained:

- Replace the Cylinder Block Coolant Valve (N545): Refer to the Repair Information.

If the specified value was obtained:

Checking voltage supply

Switch the ignition On.

- Using a multimeter, check the Cylinder Block Coolant Valve (N545) electrical connector terminal 1 to Ground for voltage.

Specified value: Battery voltage.

Switch the ignition Off.

If the specified value was not obtained:

- Check the wiring from the Cylinder Block Coolant Valve (N545) electrical connector terminal 1 to fuse S12 for an open, short or high resistance. Refer to Wiring Diagram for circuit detail.

- Check the electrical harness connector for damage, corrosion, lose or broken terminals.

- If necessary, repair the wiring connection.

If the specified value was obtained:

Checking wiring

- Remove the Engine Control Module (ECM) (J623). Refer to the Repair Information.

- Using a multimeter, check the Cylinder Block Coolant Valve (N545) electrical harness connector terminal 2 to the Engine Control Module (ECM) (J623) electrical harness connector for resistance.






Specified value: 1.5 ohms Max.

If the specification was not obtained:

- Check the wiring for a short, high resistance or an open circuit.

- Check the electrical harness connector for damage, corrosion, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring, the voltage was present and the solenoid resistance check was OK:

- Replace the Engine Control Module (ECM) (J623). Refer to the Repair Information.

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.