Exhaust Gas Temperature Sensor 1 - 4, Checking

Diagnostic Procedures

Exhaust Gas Temperature Sensor 1 - 4, Checking

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

View 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 engine MUST be at room temperature to read the resistance of the Exhaust Gas Temperature Sensor. Exhaust system must be cool to touch.

Test procedure

- Disconnect the Exhaust Gas Temperature Sensor harness connector.

- Measure the resistance of the 2 terminals of the Exhaust Gas Temperature Sensor connector.

Specified value: 215 ohms (± 25 ohm).

If the specified value was not obtained:

- Replace the Exhaust Gas Temperature Sensor.

If the specified value was obtained:

- Connect the voltmeter to terminal 1 of the Exhaust Gas Temperature Sensor harness connector and ground black lead to engine.

- Turn the ignition switch ON.

Specified value: 3.35 V (±.5 V).

If the specified value was obtained:

- Leave the red lead on terminal 1 and connect the black lead to terminal 2.

Specified value: 3.35 V (±.5 V).

If any of the specified values were Not obtained:

- Remove the Motronic Engine Control Module (ECM) (J623).

- Using a multimeter, check the Exhaust Gas Temperature Sensor electrical harness connector terminals to the Motronic Engine Control Module (ECM) (J623) electrical harness connector T94 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:

- Replace the Motronic Engine Control Module (ECM) (J623).

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.