Reducing Agent Reversing Valve Checking

Reducing Agent Reversing Valve Checking

Observe all safety precautions: => [ Safety Precautions ] Safety Precautions

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

Prior to repair work, perform a preliminary check to verify the condition. Refer to => [ 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.

• Wiring diagram.

Test requirements

• Fuse S14 is OK

• The ignition switched Off.

Start diagnosis

- Disconnect the T8 electrical harness connector located on the left side frame rail near the rear axle.

Checking resistance

- Using a multimeter, measure the resistance of the Reduction Agent Reversing Valve (N473) terminals T8/1 to T8/3 (male terminal connector).

Specified value: 11.4 ohms (+/- 2.5 ohms)

If the specified value was Not obtained:

- Replace the Reduction Agent Reversing Valve (N473). Refer to the service information for removal and installation procedures.

If the specified value was obtained:

Checking voltage

- Turn the ignition switch ON.

- Measure the voltage of the Reduction Agent Reversing Valve (N473) harness connector (female terminals) T8/1 to Ground.

Specified value: 3.50 V (+/- 0.9 V)

- Measure the voltage of the Reduction Agent Reversing Valve (N473) harness connector (female terminals) T8/3 to Ground.

Specified value: Battery voltage

If any of the specified values were Not obtained:

- Check the wiring for a short circuit to each other, Battery positive, Ground or high resistance.

- If necessary, repair the faulty wiring connection.

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

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 Reduction Agent Reversing Valve (N473) electrical harness connector to the Engine Control Module (ECM) (J623) electrical harness T91 connector for resistance. Refer to Wiring Diagrams for detail.






Specified value: 1.5 ohms Max.

If the specification was not obtained:

- Check the wiring for a short circuit to each other, Battery positive, Ground or high resistance.

- If necessary, repair the faulty wiring connection.

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

If no malfunction is detected in the wiring and the voltage readings were Not correct:

- Replace the Engine Control Module (ECM) (J623). Refer to the service information 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 ] Monitors, Trips, Drive Cycles and Readiness Codes.