Possible Causes
WARNING: This page is about a different car, the 2002 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
Possible causes are:
- Shorts to VPWR in harness or HO2S.
- Water in connectors (contamination).
- Open VPWR circuit.
- Open ground circuit.
- Low battery voltage.
- Corrosion or poor mating materials and wiring.
- Damaged HO2S heater.
- Damaged PCM.