EGR Cooler Switch Over Valve 1&2, Checking

EGR Cooler Switch Over Valve 1&2, Checking

Observe all safety precautions: => [ Safety Precautions ] Generic Scan Tool

View clean working conditions: => [ Clean Working Conditions ] Clean Working Conditions

Perform a preliminary check to verify the condition: => [ Preliminary Check ] Preliminary Check.

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.

Special tools, testers and auxiliary items required

• Multimeter

• Electrical connector test lead set

Test conditions

• Battery voltage 12.5 V

• Fuse OK

• Ignition switched off

• The EGR Cooler Switch-Over Valve 1 or 2 are solenoids that control vacuum motors to each EGR cooler (main and auxiliary). The N345 (solenoid) is located on top of the engine to the left (drivers side) of center. N 381 (solenoid) is located on the left (drivers side) at the rear of the cylinder head.

Test procedure

- Disconnect the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381) harness connector.

- Turn the ignition switch ON.

- Measure the resistance of the 2 terminals of the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381) connector.

Specified value: 35.2 ohms (+/- 6 ohms).

If the specified value was not obtained:

- Replace the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381). Refer to the Repair Manual.

If the specified value was obtained:

Checking voltage

- Connect the voltmeter to terminal 1 of the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381) harness connector and ground black lead to engine ground.

Specified value: 11.60 V (+/- 1.5 V).

If the specified value was obtained:

- Connect the voltmeter to terminal 2 of the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381) harness connector and ground black lead to engine ground.

Specified value: 3.48 V (+/-.5 V).

If any of the specified values were Not obtained:

Checking wiring

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

- Using a multimeter, check the EGR Cooler Switch Over Valve 1 or 2 (N345 / N381) electrical harness connector terminals to the Engine Control Module (ECM) (J623) electrical harness connector T105 connector for resistance.






Specified value: 1.5 ohms Max.

If any of the specified values were Not obtained:

- Check the wires for a short circuit to each other, a short to battery voltage, or a short to ground.

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

- Repair as necessary.

If no malfunction is detected in electrical circuit and the voltage was Not obtained:

- Replace the Engine Control Module (ECM) (J623). Refer to the appropriate repair manual for removal and installation procedures.

Final procedures

After the 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 ] Programming and Relearning.