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Home >> Ford >> 2005 >> Excursion 6.0 P, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests - 6.0L Diesel (99P F450/550) >> Pinpoint Test K: Engine Coolant Temperature (ECT) Sensor >> Test Procedure

Test Procedure

  1. K1 PRELIMINARY DIAGNOSIS FOR DTCS P0117 OR P0118 
    • Carry out a visual inspection.
    • Retrieve and record all DTCs.
    • Record the freeze frame data.
    • Clear all the DTCs.
    • Carry out the on-demand self-test.

    Are DTCs P0117 or P0118 present? 

    Yes No
    For DTC P0117, GO to  K2.
    For DTC P0118, GO to  K4.    		 UNABLE to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the fault. REPAIR as necessary. REFER to SYMPTOM CHARTS - 6.0L DIESEL if a driveability concern exists.
  2. K2 DIAGNOSTIC TROUBLE CODE (DTC) P0117 
    • Possible causes:
      • ECT signal circuit ground short
      • ECT sensor
      • PCM
    • Simulate opposite DTC.
    • Key OFF.
    • Disconnect the ECT harness connector.
    • Key ON, engine OFF.
    • Carry out the KOEO on-demand self-test.

    Is DTC P0118 present? 

    Yes No
    INSTALL a new ECT sensor. CLEAR the DTCs. REPEAT the self-test. GO to  K3.
  3. K3 CHECK THE ECT SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    • Key OFF.
    • Disconnect the PCM engine connector.
    • Measure the resistance between the ECT harness signal circuit pin 2, harness side and ground.

    Is the resistance greater than 10,000 ohms? 

    Yes No
    INSTALL a new PCM. CLEAR the DTCs. REPEAT the self-test. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  4. K4 DIAGNOSTIC TROUBLE CODE (DTC) P0118 
    • Possible causes:
      • ECT signal circuit open or short to voltage
      • signal return circuit open
      • ECT sensor
      • PCM
    • Simulate opposite DTC.
    • Key OFF.
    • Connect a 5-amp fused jumper wire between the ECT sensor signal circuit pin 2, harness side and the ECT sensor signal return circuit pin 1, harness side.
    • Key ON, engine OFF.
    • Carry out the KOEO on-demand self-test.

    Is DTC P0117 present? 

    Yes No
    INSTALL a new ECT sensor. CLEAR the DTCs. REPEAT the self-test. GO to  K5.
  5. K5 CHECK THE ECT SIGNAL CIRCUIT FOR AN OPEN 
    • Key OFF.
    • Disconnect the PCM engine connector.
    • Measure the resistance between the PCM engine connector pin 32, harness side and the ECT sensor signal circuit pin 2, harness side.

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  K6. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  6. K6 CHECK THE ECT SIGNAL RETURN CIRCUIT FOR AN OPEN 
    • Measure the resistance between the PCM engine connector pin 25, harness side and the ECT sensor signal return circuit pin 1, harness side.

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  K7. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  7. K7 CHECK THE ECT SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE 
    • Key ON, engine OFF.
    • Measure the voltage between the ECT sensor signal circuit pin 2, harness side and ground.

    Is any voltage indicated? 

    Yes No
    REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. INSTALL a new PCM. CLEAR the DTCs. REPEAT the self-test.
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