Oxygen Sensor Signal Wiring and Actuation, Checking
Oxygen sensor signal wiring and actuation, checking
NOTE: The oxygen sensor signal is monitored by the On Board Diagnostic (OBD) system.
- Check DTC memory.
- If a DTC related to oxygen sensor is displayed and oxygen sensor heating is OK unplug connector for relevant oxygen sensor.
- Check voltage by connecting hand-held multimeter VAG 1526 (measuring range 2 V) between sockets 3 and 4 of plug on wiring harness.
- Switch ignition on.
Specified value: 450 +/- 50 mV.
If specified value is not attained:
- Check oxygen sensor wires:
Heated Oxygen Sensor (HO2S) -G39-
Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-
Heated Oxygen Sensor (HO2S) 2 -G108-
Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131-
If specified value is attained:
- Replace oxygen sensor.
Checking oxygen sensor wiring, Heated Oxygen Sensor (HO2S) -G39-
- Unplug 4-pin connector (black) to -G39-.
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Test for open circuit in following wiring connections.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
3 51
4 70
Wire resistance: max. 1.5 Ohm
- Also test wires on 4-pin connection for shorts between them.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 51
Specified value: infinite resistance (open circuit)
- Test screen wiring for short to oxygen sensor wiring.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 32 or 2
3 32 or 2
Specified value: infinite resistance (open circuit)
If no wiring malfunction is detected:
- Replace Motronic Engine Control Module (ECM) -J220-.
Checking oxygen sensor wiring, Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-
- Unplug 4-pin connector for -G130-.
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Test for open circuit in following wiring connections.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
3 68
4 69
Wire resistance: max. 1.5 Ohm
- Also test wires on 4-pin connector for shorts between them.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 68
Specified value: infinite resistance (open circuit)
- Test screen wiring for short to oxygen sensor wiring.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 32 or 2
3 32 0r 2
Specified value: infinite resistance (open circuit)
If no wiring malfunction is detected:
- Replace Motronic Engine Control Module (ECM) -J220-.
Checking oxygen sensor wiring, Heated Oxygen Sensor (HO2S) 2 -G108-
- Unplug 4-pin connector (black) to -G108-.
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Test for open circuit in following wiring connections.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
3 12
4 13
Wire resistance: max. 1.5 Ohm
- Also test wires on 4-pin connector for shorts between them
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 12
Specified value: infinite resistance (open circuit)
- Test screen wiring for short to oxygen sensor wiring.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 32 or 2
3 32 or 2
Specified value: infinite resistance (open circuit)
If no wiring malfunction is detected:
- Replace Motronic Engine Control Module (ECM) -J220-.
Checking oxygen sensor wiring, Oxygen Sensor (O2S) 2 -G131- Behind Three Way Catalytic Converter (TWC)
- Disconnect 4-pin connector for -G131-.
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Test for open circuit in following wiring connections.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
3 10
4 11
Wire resistance: max. 1.5 Ohm
- Also test wires on 4-pin connector for shorts between them.
Connector on
wiring harness, socket Test box VAG 1598/31 socket
4 10
Specified value: infinite resistance (open circuit)
- Test screen wiring for short to oxygen sensor wiring.
Specified value: infinite resistance (open circuit)
If no wiring malfunction is detected:
- Replace Motronic Engine Control Module (ECM) -J220-.