Oxygen Sensor Behind Three Way Catalytic Converter G130, Checking

Oxygen Sensor Behind Three Way Catalytic Converter G130, Checking

NOTE:
- Vehicle must be raised before the electrical connector for the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 is accessible.
- When servicing terminals in the electrical harness connector of the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130, use only gold-plated terminals.

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

Test requirements
- Fuse SB46 OK.
- The Motronic Engine Control Module (ECM) Power Supply Relay 2 J670 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.
- Ignition switched off.

Test procedure
- Perform a preliminary check to verify the customers complaint. Preliminary Check

Function test
- Perform the function test in Diagnostic Mode 06.

If the specified values are not obtained:

Start diagnosis
- Raise the vehicle.







- Remove the right vehicle floor cover - arrows -.

Checking primary voltage







- Disconnect the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 electrical harness connector - arrow -.







- Using a multimeter, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 electrical harness connector terminals 3 to 4 for voltage.
- Crank the engine.

Specified value: 0.4 to 0.5 Volts

- Switch the ignition off.

If the specified value was obtained:
- Replace the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130.

If the specified value was not 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 Motronic Engine Control Module (ECM) J623.







- Using a Multimeter, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 electrical harness connector terminals to the Motronic Engine Control Module (ECM) J623 electrical harness connector T94 terminals for an open circuit.


Oxygen Sensor (O2S) Behind Motronic Engine Control Module
Three Way Catalytic Converter (ECM) J623 electrical connector
(TWC) G130 electrical harness T94 terminals or test box sockets
connector terminals
3 76
4 77

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, loose or broken terminals.
- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring:
- Erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory.
- Perform a road test to verify repair.

If the DTC does not return:
Repair complete, Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
- End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was not OK:
- Replace the Motronic Engine Control Module (ECM) J623.
- 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. 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