Component Tests and General Diagnostics

Checking Operation of Oxygen Sensor





- Run engine approx. 30 seconds at a speed of 3,000 rpm before checking.
- If checking is not finished after about 5 minutes, heat oxygen sensor by running engine approx. 30 seconds at 3,000 rpm again.
- Connect mixture control unit 12 6 400 on the diagnosis plug.
- Oxygen sensor is okay, if the LED (1) flashes at least every 3 seconds after waiting approx. 10 seconds.

LED Does Not Flash (Oxygen Sensor Not Operating):
- Oxygen sensor is dirty (oil/soot) or does not have correct operating temperature = 350°C (662°F).
- Heat oxygen sensor again by running engine at fast speed.