Possible Causes
WARNING: This page is about a different car, the 2003 Mazda Protege5 and 2003 Mazda Protege. However, it is still accessible from the selected car via links, so may be relevant.
- ECT signal and ground circuits are shorted to each other.
- ECT sensor malfunction.
- PCM malfunction.
- Short circuit between ECT sensor and PCM.