Oxygen Sensor Behind TWC Signal Wiring and Connections Checking

Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) Signal Wiring And Wiring Connections, Checking

Component locations


NOTE: Heated oxygen sensor signals are monitored by the On Board Diagnostic (OBD) system.


- Check Diagnostic Trouble Code (DTC) memory.

If O2S malfunctions are indicated but O2S heating is OK:
- Disconnect oxygen sensor.







- Connect multimeter US 1119 (Fluke 83 or equivalent), set to 2 VDC measuring range, and check voltage between harness connector terminals 3 and 4.
- Switch ignition on.
Specified value: 450 ± 50 mV (behind TWC)

If voltage is not OK:
- Connect VAG1598/19 test box to Engine Control Module (ECM) harness connector. Refer "Scan Tool Testing/Scan Tool Connecting and Initial Checks/VAG1598/19 Test Box, Connecting" Testing and Inspection


- Check wiring connections for open circuit, short circuit to B+, and short circuit to Ground:


NOTE:
- Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC) -G130- (bank 1)
- Oxygen Sensor (O2S) 2 behind Three Way Catalytic Converter (TWC) -G131- (bank 2)


O2S behind TWC VAG1598/19 test box socket (ECM terminal)
connector terminal
3 (G130) C17
4 (G130) C21
3 (G131) C18
4 (G131) C20







- If wiring is OK, replace Engine Control Module (ECM).