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NOX Sensor Control Module 1 - 2, 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 .

The NOx Sensor and NOx Module are combined and must be serviced as a unit.

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 

Test Procedure 

-- Disconnect the NOx sensor electrical harness connector.

Checking voltage and ground

Turn the ignition ON.

-- Using a multimeter, measure the voltage between the NOx Sensor Module -J583/J881- terminal 1 to ground.

Specified value: Battery voltage.

Turn the ignition OFF.

If the specified value was not obtained:

-- Check the circuit for a short to ground, open circuit or high resistance.

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

-- Repair as necessary.

If no malfunction is found in the wiring:

-- Connect the red voltmeter lead to Battery voltage, and the black lead to terminal 2 of J583 (also test terminal 5 of J881) of the NOx Sensor Module -J583/J881-

Specified value: Battery voltage.

If the specified value was not obtained:

-- Check the circuit for an open circuit or high resistance.

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

-- Repair as necessary.

If the specified value was obtained:

Checking CAN Bus wiring

NOTE: Do not disconnect more than 1 NOx module when checking the following circuits as the test results will be in error.

-- Turn the ignition ON.

-- Connect the red voltmeter lead to terminal 3 of the NOx Sensor Module -J583/J881-

and the black lead to ground.

Specified value: near 2.48 V.

-- Connect the red voltmeter lead to terminal 4 of the NOx Sensor Module -J583/J881-

and the black lead to ground.

Specified value: near 2.52 V.

Turn the ignition OFF.

If any of the specified values were not obtained:

-- Check the CAN bus circuit for an open or high resistance between the NOx module and the ECM.

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

-- Repair as necessary.

If the specified values were obtained:

-- Replace the NOx Sensor Module -J583/J881-. Refer to the service information for removal and installation procedures.

If any of the specified values were Not obtained and the wiring has no faults:

-- Replace the Engine Control Module -J623-. Refer to the service information for removal and installation procedures.

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 .
  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 .