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DTC P0125

DTC P0125  : ECT Sensor 1 Malfunction/Slow Response

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0125 ECT Sensor 1 Malfunction/Slow Response    

DTC (PGM-FI)

  1. ECT sensor 1 check

    -1. Enter the maintenance mode, then start the engine , and let it idle for 20 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 deg.F    
    Less than -18 deg.C

    Data List

    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 .

    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. Enter the maintenance mode, then start the engine .

    -4. 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    

    Data List

    -5. 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

    Data List

    Do the current condition(s) match the threshold?

    YES 

    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 on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

    NO 

    The failure is duplicated. Go to step 3.

  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 .

    NO 

    Replace the thermostat .