Additional Information

Fig. 2 Cycle:

Additional Information
1. Vehicle Harness Check
- Check for open and short circuit in harness / connector between HO2S and ECM.
- Check for approx. 12V between heater harness.
2. Heater Resistance Check
- Check resistance between the heater terminals; should read 10ohms to 20ohms at -20°C to 100°C.
3. Performance Check
- Run the engine at 2500 RPM for two minutes, to heat up the HO2S.
- Check the voltage of the sensor output: Alternates between less than 0.4V at feed back engine conditions and in excess of O.5V.
- Check the cycle of the front sensor output; should read 15 cycles per minute or more at 1500 RPM
- Check the cycle of the rear sensor output; should read 1 cycle per 3 minutes or more at 1500 RPM