Heated Oxygen Sensor 2 and Sensor Regulation Before Catalytic Converter, Checking

Heated Oxygen Sensor 2 And Sensor Regulation Before Catalytic Converter, Checking

The following procedure is used to diagnose Heated Oxygen Sensor (HO2S) 2 G108 which is controlled by the Engine Control Module (ECM) 2 J624.

NOTE: Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Heated Oxygen Sensor (HO2S) 2 G108.

Special tools, testers and auxiliary items required
- Multimeter.
- Wiring diagram.

Test requirements
- The Engine Control Module (ECM) 2 J624 fuses OK.
- The Oxygen Sensor (O2S) 2 Heater Z28 before catalytic converter OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Exhaust system between catalytic converter and cylinder head properly sealed.
- Coolant Temperature at least 80 degrees C.

Function test
- Perform the function test located in diagnostic mode 06.

If specified values are obtained:
- End diagnosis and switch the ignition off.

If the specified values are not obtained:

Test procedure
- Perform a preliminary check to verify the customers complaint. General Diagnosis

Start diagnosis
- Raise the vehicle.







- Disconnect the black Heated Oxygen Sensor (HO2S) 2 G108 - 4 -.

Checking primary voltage







- Using a multimeter , check the Heated Oxygen Sensor (HO2S) 2 G108 electrical harness connector terminals 2 to 6 for voltage.

Specified value: 0.400 to 0.500 Volts

- Switch the ignition off.

If the specified value was not obtained:
- Replace the Heated Oxygen Sensor (HO2S) 2 G108.

If the specified value was obtained:

Checking wiring

If the manufacturers test box is being used. Perform the following step.
- Install the test box.

If the manufacturers test box is not being used. Perform the following step.
- Remove the Engine Control Module (ECM) 2 J624.







- Using a Multimeter , check the Heated Oxygen Sensor (HO2S) 2 G108 electrical harness connector terminals to the Engine Control Module (ECM) 2 J624 electrical harness connector T94a terminals for an open circuit.

Heated Oxygen Sensor (HO2S) Engine Control Module
2 G108 electrical harness (ECM) 2 J624 electrical
connector terminals connector T94a terminals or
test box sockets
1 60
2 61
5 81
6 82

Specified value: 1.5 Ohms Max.

If the specification was not obtained:
- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring:
- Replace the Engine Control Module (ECM) 2 J624.

Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. If necessary, erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. If the DTC memory was erased, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

- End of diagnosis.