Oxygen Sensor Signal Wire and Activation, Checking

Oxygen Sensor Signal Wire and Activation, Checking


NOTE: The oxygen sensor signal is monitored by the OBD system.


- Check DTC memory.
- If malfunction related to the oxygen sensor is displayed and the oxygen sensor heater is OK, disconnect harness connector for relevant oxygen sensor.

Component location of 4-pin harness connector of oxygen sensor.







- Test voltage by connecting hand-held multimeter Fluke 83 (or equivalent) (measuring range 2 V) between sockets 3 and 4 of connector on wiring harness.
- Switch ignition on. Specification: 450 ± 50 mV.

If the specification is not obtained, check oxygen sensor wiring:

Bank 1, Sensor 1.
Bank 1, Sensor 2.
Bank 2, Sensor 1.
Bank 2, Sensor 2.

If specification is obtained:
- Replace relevant oxygen sensor.

Checking oxygen sensor wiring for Heated Oxygen Sensor (HO2S) -G39
Component location of 4-pin harness connector of oxygen sensor.
- Disconnect 4-pin connector (black) for Heated Oxygen Sensor (HO2S) -G39.
- Connect VAG1598/31 test box to wiring harness for engine control module. Do not connect to engine control module itself. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG1598/31 Test Box" Testing and Inspection







- Check following wiring connections for open circuits:

Connector on VAG1598/31 test box
wiring harness, socket socket
3 51
4 70

Resistance in wiring: max. 1.5 Ohm







- Check wiring on 4-pin connector for short circuits to each other.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 51

Specification: infinite ohms (open circuit)

- Check shielded wire for short circuit to sensor wiring.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 32
3 32

Specification: infinite ohms (open circuit)

If no malfunctions are identified in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220.

Checking wiring for Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130
Component location of 4-pin harness connector of oxygen sensor.

- Disconnect 4-pin connector (black) for Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130.
- Connect VAG1598/31 test box to wiring harness for engine control module. Do not connect to the engine control module itself. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG1598/31 Test Box" Testing and Inspection







- Check following wiring connections for open circuits:

Connector on VAG1598/31 test box
wiring harness, socket socket
3 68
4 69

Resistance in wiring: max. 1.5 ohm







- Check wires on 4-pin connector for short circuits with each other.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 68

Specification: infinite ohms (open circuit)

- Check shielded wire for short circuit to sensor wiring.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 32
3 32

Specification: infinite ohms (open circuit)

If no malfunctions are identified in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220.

Checking wiring for Heated Oxygen Sensor (HO2S) 2 -G108
Component location of 4-pin harness connector of oxygen sensor.
- Disconnect 4-pin connector (black) for Heated Oxygen Sensor (HO2S) 2 -G108.
- Connect VAG1598/31 test box to wiring harness for engine control module. Do not connect to the engine control module itself. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG1598/31 Test Box" Testing and Inspection







- Check following wiring connections for open circuits:

Connector on VAG1598/31 test box
wiring harness, socket socket
3 12
4 13

Resistance in wiring: max. 1.5 ohm







- Check wires on 4-pin connector for short circuits to each other.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 12

Specification: infinite ohms (open circuit)

- Check shielded wire for short circuit to sensor wiring.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 32
3 32

Specification: infinite ohms (open circuit)

If no malfunctions are identified in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220.

Checking wiring for Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131
Component location of 4-pin harness connector of oxygen sensor.
- Disconnect 4-pin connector for Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131
- Connect VAG1598/31 test box to wiring harness for engine control module. Do not connect to the engine control module itself. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG1598/31 Test Box" Testing and Inspection







- Check following wiring connections for open circuits:

Connector on VAG1598/31 test box
wiring harness,socket socket
3 10
4 11

Resistance in wiring: max. 1.5 ohm







- Check wires on 4-pin connector for short circuits to each other.

Connector on VAG1598/31 test box
wiring harness, socket socket
4 10

Specification: infinite ohms (open circuit)

- Check shielded wire for short circuit to sensor wiring.

Connector on VAG1598/31 test box
wiring harness, socket socket

4 32
3 32

Specification: infinite ohms (open circuit)

If no malfunctions are identified in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220.

If no malfunction can be identified in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220.
- Display readiness code. The readiness code must be regenerated if the DTC memory was erased.
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Readiness Code" Testing and Inspection
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Generating Readiness Code" Testing and Inspection