DTC P0125: ECT Sensor 1 Malfunction/Slow Response

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions SystemsHow to Troubleshoot the CVT System(CVT System) .

DTC (PGM-FI)

• 1. ECT sensor 1 check:

  - 1. Start the engine, and let it idle for 5 minutes or more.

  - 2. Check the parameter(s) below with the HDS.

  Signal	Threshold		Current conditions
  	Values	Unit	Values	Unit
  ECT SENSOR 1	Less than 0	°F

  Do the current condition(s) match the threshold?

  YES 

  Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM. If they are OK, replace ECT sensor 1 - Refer to: ECT Sensor 1 Removal and InstallationECT Sensor 2 Removal and Installation .

  NO 

  Go to step 2.

• 2. Problem verification:

  - 1. Turn the vehicle to the OFF (LOCK) mode.

  - 2. Allow the engine to cool to 104°F (40°C) or less.

  - 3. Start the engine, and let it idle until ECT SENSOR 1 goes up to about 158°F (70°C).

  Signal	Current conditions
  	Values	Unit
  ECT SENSOR 1

  - 4. Check the parameter(s) below with the HDS.

  Signal	Threshold		Current conditions
  	Values	Unit	Values	Unit
  ECT SENSOR 2	About 158	°F

  Do the current condition(s) match the threshold?

  YES 

  The failure is duplicated. Go to step 3.

  NO 

  Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

• 3. Thermostat check:

  - 1. Check the thermostat .

  Is the thermostat OK?

  YES 

  Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM. If the connections and terminals are OK, replace ECT sensor 1 - Refer to: ECT Sensor 1 Removal and InstallationECT Sensor 2 Removal and Installation .

  NO 

  Replace the thermostat .