Note. If DTCs P0110, P0115, P0120 and P0450 are output together, check circuit E2 (Blue/Black wire) between terminal No. 9 at ECM harness connector E6 and splice I11. Repair as necessary. See appropriate wiring diagram in WIRING DIAGRAMS article.
Circuit Description
ECT sensor is a thermistor sensor which monitors water temperature. DTC is set when ECM detects an open or short in ECT sensor circuit. Possible causes are
- ECT sensor circuit is open or shorted.
- Defective ECT sensor.
- Defective ECM.
Diagnostic Aids
After confirming DTC P0115, use scan tool to access CURRENT DATA to confirm engine coolant temperature. If temperature displayed on scan tool is -40°F (-40°C), ECT sensor circuit may be open. If temperature displayed on scan tool is 284°F (140°C) or more, ECT sensor circuit may be shorted. Using scan tool, read freeze frame data. Freeze frame records engine conditions when malfunction is detected.