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DTC P0117

DTC P0117  ECT sensor circuit low input 
DETECTION CONDITION 
  • The PCM monitors the ECT sensor signal at PCM terminal 2AH. If the PCM detects the ECT sensor voltage below 0.2 V for 5s  , the PCM determines that the ECT sensor circuit has malfunction.

Diagnostic support note 
  • This is a continuous monitor (engine cooling system).
  • The MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Engine overheating (Cooling system malfunction)
  • ECT sensor connector or terminals malfunction
  • ECT sensor malfunction
  • Short to ground in wiring harness between ECT sensor terminal A and PCM terminal 2AH
  • PCM connector or terminals malfunction
  • ECT sensor signal circuit and ground circuit are shorted to each other
  • PCM malfunction
G07877613
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (engine cooling system related) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 VERIFY RELATED SERVICE BULLETINS AVAILABILITY 
  • Verify related Service Bulletins availability.
  • Is any related Service Bulletins available?
 Yes Perform the repair or diagnosis according to the available Service Bulletins.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY ENGINE CONDITION 
  • Is the engine overheating?
 Yes Perform the symptom troubleshooting "NO. 17 COOLING SYSTEM CONCERNS-OVERHEATING".
(See NO. 17 COOLING SYSTEM CONCERNS-OVERHEATING ).
No Go to the next step.
4 INSPECT ECT SENSOR CONNECTOR AND TERMINALS 
  • Turn the ignition switch off.
  • Disconnect the ECT sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 9.
No Go to the next step.
5 CLASSIFY ECT SENSOR MALFUNCTION OR WIRING HARNESS MALFUNCTION 
  • Reconnect the ECT sensor connector.
  • Access the ECT PID.
  • Verify the ECT value when disconnecting ECT sensor connector.
  • Does the ECT value change?
 Yes Replace the ECT sensor, then go to Step 9.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
6 INSPECT ECT SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • Disconnect the ECT sensor connector.
  • Inspect for continuity between ECT sensor terminal A (wiring harness-side) and body ground.
  • Is there continuity?
 Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:

Go to Step 9.
No Go to the next step.
7 INSPECT PCM CONNECTOR AND TERMINALS 
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 9.
No Go to the next step.
8 INSPECT ECT SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER 
  • ECT sensor and PCM connectors are disconnected.
  • Inspect for continuity between ECT sensor terminals A and B (wiring harness-side).
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to each other, then go to the next step.
No Go to the next step.
9 VERIFY TROUBLESHOOTING OF DTC P0117 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.
  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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