| CAUTION | If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction. |
Circuit Description
The ECT sensor is a thermistor that monitors coolant temperature. If DTC P0115 is set, ECM will operate in a fail-safe mode, in which engine coolant is assumed to be 176°F (80°C). DTC P0115 is set when ECM detects a open or short in ECT sensor circuit. Possible causes are
- ECT Sensor Open Or Short Circuit
- ECT Sensor
- ECM
Note. If DTCs P0110, P0115, P0120 and P1410 are output together, inspect ECM terminal E2 (ground) circuit for an open. Repair as necessary. See appropriate wiring diagram in SYSTEM WIRING DIAGRAMS article.