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Diagnostic procedure

DTC P0125 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (Engine cooling system related) been recorded?
 Yes Go to the next step.
No Record FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to the next step.
2 VERIFY RELATED SERVICE INFORMATION AVAILABILITY 
  • Verify related Service Information availability.
  • Is any related Service Information available?
 Yes Perform repair or diagnosis according to available Service Information.
  • If vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY CURRENT INPUT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT 
  • Start the engine.
  • Warm up the engine completely.
  • Access ECT PID using the WDS or equivalent.
  • Is ECT PID above 60 °C {140 °F}? 
 Yes Intermittent concern exists. Go to INTERMITTENT CONCERNS TROUBLESHOOTING procedure.
(See INTERMITTENT CONCERN TROUBLESHOOTING .)
No Go to the next step.
4 INSPECT POOR CONNECTION OF ECT SENSOR CONNECTOR 
  • Turn the ignition switch off.
  • 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 terminal, then go to Step 7.
No Go to the next step.
5 INSPECT ECT SENSOR  Yes Go to the next step.
No Replace the ECT sensor, then go to Step 7.
6 INSPECT POOR CONNECTION OF PCM CONNECTOR 
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/ pulled-out pins, corrosion.)
  • Is there any malfunction?
 Yes Repair or replace the terminal, then go to the next step.
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0125 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Turn the ignition switch to the ON position (Engine off).
  • Access ECT PID using the WDS or equivalent.
  • Wait until ECT PID below 8 °C {46 °F} (1) /below 19°C{66°F} (2) 
  • Start the engine and warm it up completely.
  • Is the PENDING CODE for this DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC troubleshooting.
(See DTC TABLE )
No Troubleshooting completed.
(1) California emission regulation applicable model
(2) Except for California emission regulation applicable model
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