DTC P0125

DTC P0125  : ECT Sensor 1 Malfunction/Slow Response

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 10	deg.F
   	Less than -12	deg.C

   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 , then do the repair verification.

   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 deg.F (40 deg.C) or less.

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

   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.

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 , then do the repair verification.

   NO 

   Replace the thermostat , then do the repair verification.

4. Repair verification

   -1. Turn the vehicle to the ON mode.

   -2. Reset the PCM with the HDS .

   Reset PCM

   -3. Turn the vehicle to the OFF (LOCK) mode.

   -4. Allow the engine to cool to 104 deg.F (40 deg.C) or less.

   -5. Start the engine, and let it idle until ECT SENSOR 1 goes up to about 158 deg.F (70 deg.C).

   Signal	Current conditions
   	Values	Unit
   ECT SENSOR 1

   -6. Check the parameter(s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   ECT SENSOR 2	About 158	deg.F
   	About 70	deg.C

   DTC (PGM-FI)

   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, go to step 1.

   NO 

   Troubleshooting is complete. If the PCM was substituted, replace the original PCM . If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.