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With Generic Scan Tool



Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC), checking

The following procedure is used to diagnose both Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 and the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131.

Note: When servicing terminals in the electrical harness connector of the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 and Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131 , use only gold-plated terminals.

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

Test requirements
- The Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 and Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131 fuses Ok.
- Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 and Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131 Heater circuits OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, selector lever in position "P" or "N".
- 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�C.

Test procedure

- Perform a preliminary check to verify the customers complaint.

Start diagnosis

Function test

- Perform the function test in Diagnostic Mode 06. Diagnostic Mode 06: Checking Test Results of Components That Are Not Continuously Monitored

If the specified values are obtained:

- End diagnosis and switch ignition off.

If the specified values are not obtained:

Checking primary voltage






- Disconnect the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 electrical harness connector - Upper Arrow - or the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131 electrical harness connector - Lower Arrow - .






or

- Switch the ignition on.






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

Specified value: 0.400 to 0.500 Volts

- Switch the ignition off.

If the specified value was obtained:

- Replace the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 or Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131.

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 80 Pin VAG1598/22 (Engine Code AHA). [1][2]Scan Tool Connecting and Initial Checks

If the manufacturers test box is not being used. Perform the following step.

- Remove the Engine Control Module (ECM) J220.






- Using a Multimeter, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) G130 electrical harness connector terminals to the Engine Control Module (ECM) J220 or Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) G131 electrical harness connector terminals for an open circuit.




(Engine Code AHA)

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: Reset/Delete Diagnostic Data

- Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Audi Drive Cycle/Readiness Code

- End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

- Replace the Engine Control Module (ECM) J220.

- Assembly is performed in the reverse of the removal.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.

End of diagnosis.
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