With Generic Scan Tool

Oxygen Sensor Heater For Oxygen Sensors Behind Three Way Catalytic Converter (TWC), Checking

NOTE: When servicing terminals in harness connector of Heated Oxygen Sensor (HO2S), use only gold-plated terminals.

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirements
- The respective fuses of Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- must be OK.
- Ignition switched off.

Engine codes AMU, ATC







- Disconnect 4-pin harness connector to Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-.







- Set multimeter for resistance measurement and connect it to terminals 1 + 2 at connector for oxygen sensor. Check oxygen sensor heater for continuity.
Specified value: 1...5 Ohm (at room temperature)

Engine codes AWP, BEA
- Disconnect 4-pin harness connector to Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-.







- Set multimeter for resistance measurement and connect it to terminals 1 + 2 at connector for oxygen sensor. Check oxygen sensor heater for continuity.
Specified value: 6.4...47.5 Ohm (at room temperature)

Continuation for all vehicles
If an open circuit is found in the oxygen sensor heater:
- Replace Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-.

If oxygen sensor heater has continuity:
- Check voltage supply and wiring

Checking voltage supply and wiring







- Set multimeter for voltage measurement and connect it to terminals 1 + 2 at connector to control module.
- Start engine, and let run at idle.
- Measure voltage supply
Specified value: oscillating between 0.0 and 12.0 V

If there is no voltage:
- Connect multimeter to terminal 1 of connector and engine Ground (GND) for voltage measurement.
- Operate starter briefly.
Specified value: approx. battery voltage

If there is no voltage again:
- Check wire connection from terminal 1 to Fuel Pump (FP) Relay -J17- according to wiring diagram.

If voltage was approximately same as battery voltage:
- Switch ignition off.
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test

Engine Control Module (ECM) is not connected.







- Check wire between test box and 4-pin connector for open circuit according to wiring diagram.
Terminal 2 + socket 63
Wire resistance: max: 1.5 Ohm

If no malfunctions are found in wires:
- Replace Engine Control Module (ECM).