HO2S Front Oxygen Sensor Bank 1 Sensor 1 Checking

HO2S Front Oxygen Sensor Bank 1 Sensor 1 Checking

• Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the HO2S Oxygen Sensor Bank 1 Sensor 1 (G39) and HO2S Oxygen Sensor Bank 2 Sensor 1 (G108). No attempt should be made to repair wiring or terminals on the sensor itself. Replacement of the sensor is required in that instance.

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (S-17) fuse OK.

• The Oxygen Sensor Heater Bank 1 Sensor 1 (Z19) has not set a code. If a heater code is set, perform the Z19 heater test first.

• Battery voltage at least 12.5 volts.

• All electrical consumers such as, lights and rear window defroster, switched off.

• A/C switched off.

• Ground connections between engine/transmission/chassis OK.

• Exhaust system between catalytic converter and cylinder head properly sealed.

• Coolant Temperature at least 80° C.

Test procedure

- Observe safety precautions. Refer to => [ Safety Precautions ] Safety Precautions

- Observe Clean Working Conditions. Refer to => [ Clean Working Conditions ] Clean Working Conditions

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.

Function test

- Perform the function test in Diagnostic Mode 06. Refer to => [ Diagnostic Mode 06 - Read Test Results for Specific Diagnostic Functions ] Diagnostic Modes 01 - 09.

- Switch the ignition OFF.

If the specified values were Not obtained:

Start Diagnosis

- Disconnect the HO2S Oxygen Sensor Bank 1 Sensor 1 (G39) electrical harness connector - 2 -.





Checking primary voltage

- Switch the ignition ON.

- Using a multimeter, check the HO2S Oxygen Sensor Bank 1 Sensor 1 (G39) electrical harness connector terminals 2 to 6 for voltage.





Specified value: 0.40 to 0.50 V

- Switch the ignition OFF.

If the specified value was obtained:

- Replace the HO2S Oxygen Sensor Bank 1 Sensor 1 (G39).

If the specified value was Not obtained:

Checking wiring

- Remove the Engine Control Module (ECM) (J623). Refer to the Repair Information.

- Using a multimeter, check the HO2S Oxygen Sensor Bank 1 Sensor 1 (G39) electrical harness connector terminals to the Engine Control Module (ECM) (J623) electrical harness connector T94 terminals for an open circuit.










Specified value: 1.5 ohms Max.

If the specification was Not obtained:

- Check the wiring for high resistance, an open or a short to voltage or ground.

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

- If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring and the voltage supply was Not OK:

- Replace the Engine Control Module (ECM) (J623). Refer to the Repair Information.

- Assembly is performed in the reverse of the removal.

Final procedures

After repair work, the following work steps must be performed in the mentioned 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.