Component Tests and General Diagnostics

Checking Function of Oxygen Sensor





A. Heating Test
- Disconnect oxygen sensor plug.
- Connect ohmmeter on terminals 3 and 4 (facing oxygen sensor).
- Measure resistance.
- Specifications: < 5 ohms.

B. Signal Voltage Test
- Check "oxygen sensor voltage" in scope of DME self-diagnosis by calling oxygen sensor voltage.
- Value will be measured at idle speed with the oxygen sensor connected and oxygen sensor control switched on (approx. 1 to 2 minutes after starting the engine) and should he between 0.02 and 0.85 volts.
- The oxygen sensor is not working if a constant voltage of 0.45 volts is measured (oxygen sensor or power supply lead faulty).