NOX Sensor Control Module 1 - 2, Checking

NOX Sensor Control Module 1 - 2, Checking

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

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.

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, testers and auxiliary items required

• Multimeter

• Wiring diagram

Test requirements

• A/C switched off

• All electrical consumers switched off

• Battery voltage at least 12.5 volts

• Engine control module fuses OK

• Ground connections between engine/transmission/chassis OK

• Ignition switched off

• Vehicles with automatic transmission, shift selector lever in park or neutral

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 positive, 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 manual 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 (ECM) (J623). Refer to the service manual 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 ] 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.