Heated Oxygen Sensor and Oxygen Sensor Control after Catalytic Converter, Checking
Heated Oxygen Sensor And Oxygen Sensor Control After Catalytic Converter, Checking
NOTE: When servicing terminals in harness connector of Heated Oxygen Sensor (H02S), use only gold-plated terminals.
Recommended Special Tools, Workshop Equipment, Testers, Measuring Instruments and Auxiliary Items
- V.A.G 1526 portable multimeter or V.A.G 1715 multimeter
- Adapter set V.A.G 1594
- Wiring diagram
Test Conditions
- Corresponding Oxygen Sensor O2S Behind Three Way Catalytic Converter (TWC) -G130-fuses must be OK
- Battery voltage must be at least 11.5 V.
- All electrical consumers such as, for example, lights and rear window defroster must be switched off.
- The parking brake must be applied, otherwise the daytime running lights are switched on.
- If the vehicle is equipped with an air conditioning system, this must be switched off.
- The Ground (GND) connections between engine and body must be OK.
- Exhaust system must be properly sealed between catalytic converter and cylinder head.
- Coolant temperature must be at least 80 degrees C, Diagnostic Mode 01 - Read Current System Data Diagnostic mode 1: Check measured values; PID 5, Coolant temperature.
- Oxygen sensor heater for oxygen sensors behind catalytic converter must be OK, checking.
Function Test
- Select the following oxygen sensor test results and check whether the specified values are being reached Diagnostic Mode 05 - Read Oxygen Sensor Monitoring Test Results : Checking oxygen sensor test results.
- Check specified values for oxygen sensor test results in idle:
If the specified values are achieved:
- End diagnosis and switch ignition off.
If the specifications are not obtained:
- End diagnosis and let engine continue to run at idle.
- Check primary voltage.
Checking Primary Voltage
- Disconnect the 4-pin connector to Oxygen Sensor O2S Behind Three Way Catalytic Converter (TWC) -G130-.
- Use adapter cables from (V.A.G 1594) to connect multimeter to terminals 3 + 4 (Motronic ECM connector) for voltage measurement.
- Start engine and measure primary voltage.
Specified value: 0.40 to 0.50 V
- Switch off ignition.
If the specification is not obtained:
- Test oxygen sensor wires.
- Erase DTC memory of ECM. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Generate Readiness Code
If the specification is obtained:
- Replace Oxygen Sensor O2S Behind Three Way Catalytic Converter (TWC) -G130-.
Oxygen Sensor Wires, Checking
- Check wires between test box and 4-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Wiring resistance: max. 1.5 Ohms
Continuation for All Vehicles
- Also check wires for short circuit to B+ and Ground (GND).
Specified value: Infinity Ohms
If no fault is detected in the wiring:
- Replace Motronic Engine Control Module (ECM) -J220-