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Reduction Agent Reversing Valve Checking

Observe all safety precautions: SAFETY PRECAUTIONS 

View clean working conditions: CLEAN WORKING CONDITIONS 

Prior to repair work, perform a preliminary check to verify the condition. Refer to PRELIMINARY CHECK .

NOTE:

At the time of writing, the Reduction Agent Tank Module Assembly is replaced as a unit when an individual component of the module assembly is faulty. This may change at a later date. Check with parts for availability of components.

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 and workshop equipment required 

Test requirements 

Start diagnosis 

-- Disconnect the T/8 electrical harness connector located on the left side frame rail directly above 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 Ω (+/- 2.5 ohms)

If the specified value was not obtained, replace the Reduction Agent Tank Module Assembly.

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: 3.48 V (+/- 0.9 V)

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

Specified value: 11.40 V (+/- 2.5 V)

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 T94 connector for resistance.

Reduction Agent Reversing Valve -N473- electrical harness connector (female terminals) Engine Control Module (ECM) -J623- electrical harness connector terminals or fuse location
1 T60 / 30
3 Fuse S-14

Specified value: 1.5 Ω 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 .
  2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .