Detection Condition
WARNING: This page is about a different car, the 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
The PCM monitors Engine Coolant Temperature (ECT) sensor signal at PCM 30-pin harness connector terminal "1M" (Light Green/Black wire). If PCM detected ECT sensor voltage less than 0.20 volt, PCM determines ECT sensor circuit has malfunction. This is a Continuous Monitor (CM). MIL illuminates if PCM detects malfunction condition during first drive cycle. PENDING CODE is available if PCM detects malfunction condition. FREEZE FRAME DATA is available. DTC is stored in PCM memory.