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DTC P0116

DTC P0116  Engine coolant temperature circuit range/performance 
DETECTION CONDITION 
  • The PCM monitors the maximum value and minimum value of engine coolant temperature when the engine is started and 5 min  have been passed after leaving the vehicle 6 h or more.  If difference between maximum and minimum values of engine coolant temperature is below 6°C {10.8°F}  the PCM determines that there is an ECT circuit range/performance problem.

Diagnostic support note 
  • This is a continuous monitor (engine cooling system).
  • The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • ECT sensor connector or terminals malfunction
  • PCM connector or terminals malfunction
  • ECT sensor malfunction
  • Thermostat malfunction
  • PCM malfunction
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 arty 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 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2) 
  • Is the DTC P0116 on FREEZE FRAME DATA (Mode 2)?
 Yes Go to the next step.
No Go to the troubleshooting procedures for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE ).
4 INSPECT ECT SENSOR CONNECTOR AND TERMINALS 
  • Turn the ignition switch oft.
  • Disconnect the ECT sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 8.
No Go to the next step.
5 INSPECT PCM CONNECTOR AND TERMINALS 
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 8.
No Go to the next step.
6 INSPECT ECT SENSOR 
 Yes Replace the ECT sensor, then go to Step 8.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
7 INSPECT THERMOSTAT 
 Yes Replace the thermostat, then go to the next step.
(See THERMOSTAT REMOVAL/INSTALLATION ).
No Go to the next step.
8 VERIFY TROUBLESHOOTING OF DTC P0116 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.
  • Start the engine and warm it up to completely.
  • Is the same DTC present?
 Yes Replace PCM, then go to next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to next step.
9 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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