Possible Causes
NOTE:
Monitor description.
The engine control module monitors the ceramic temperature of the heated oxygen sensor nernst cell to ensure it is sufficiently heated after engine start
- The value of the signal measured by the engine control module is not plausible given the operating conditions
- Heated oxygen sensor circuit short circuit to ground, short circuit to power, open circuit, high resistance
- Connector is disconnected, connector pin is backed out, connector pin corrosion
- Heated oxygen sensor failure