Possible Causes
WARNING: This page is about a different car, the 2003 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0031 is set when heater current exceeds 19.7 amps while heater is operating. DTC P0032 is set when heater current is 3 amps or less while heater is operating. Possible causes are:
- Open or short in A/F sensor heater circuit.
- Defective A/F sensor heater.
- Defective ECM.