Exhaust Gas Temperature Sensor, Checking

Exhaust Gas Temperature Sensor, Checking

Special tools and equipment







- VAG1526A
- VAG1527B
- VAG1594A
- VAG1598/31

Checking voltage supply
- Switch ignition off.







- Remove engine cover (arrows).
- Disconnect connector at exhaust gas temperature sensor.







- Connect VAG1527B voltage tester as follows:

Harness connector terminal Measure to
3 Engine Ground (GND)

- Operate starter briefly.
- LED must light.

If LED does not light:
- Perform following tests marked with dots:







- Check fuse S234 (in fuse holder, position 34).
- Check wire connection from exhaust gas temperature sensor via fuse S234 (in fuse holder, socket 34) to Fuel Pump (FP) relay for open circuit:
- Check Fuel Pump (FP) relay.
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM.







- Check following wire connections for open circuit and short circuit to Ground (GND) and B+:

Harness connector VAG1598/31 test box

terminal Bushing
1 (Bank 1) 61
1 (Bank 2) 20
2 50

If wire connection is OK:
- Replace exhaust gas temperature sensor.

If the same malfunction occurs again after replacing the exhaust gas temperature sensor:
- Replace Engine Control Module (ECM).