2012 Honda Insight EXFACTORY OEM SERVICE PROCEDURE

DTC P0116: ECT Sensor 1 Range/Performance Problem

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Turn the ignition switch to ON (II).
  2. Check ECT SENSOR 1 in the DATA LIST with the HDS.

    Is about 176°F (80°C) or more, or 0.78 V or less indicated? 

    YES  -Go to step  6.

    NO  -Go to step 3.

  3. Note the value of ECT SENSOR 1 in the DATA LIST with the HDS.
  4. Start the engine. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
  5. Check ECT SENSOR 1 in the DATA LIST with the HDS.

    Does ECT SENSOR 1 change 18°F(10°C) or more? 

    YES  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the PCM.

    NO  -Go to step  11.

  6. Note the value of ECT SENSOR 1 in the DATA LIST with the HDS.
  7. Turn the ignition switch to LOCK (0).
  8. Open the hood, and let the engine cool for 3 hours.
  9. Turn the ignition switch to ON (II).
  10. Check ECT SENSOR 1 in the DATA LIST with the HDS.

    Does ECT SENSOR 1 change 18°F(10°C) or more from the value in step   6 ? 

    YES  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the PCM.

    NO  -Go to step 11.

  11. Turn the ignition switch to LOCK (0).
  12. Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ).
  13. Turn the ignition switch to ON (II).
  14. Reset the PCM with the HDS.
  15. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  16. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0116 indicated? 

    YES  -Check for poor connections or loose terminals at ECT sensor 1 and the PCM, then go to step  1.

    NO  -Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC'S TROUBLESHOOTING .

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.