Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P1116: ECT Sensor 1 Circuit Range/Performance Problem
- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
- If DTC P0111 is stored at the same time as DTC P1116, troubleshoot DTC P0111 first, then recheck for DTC P1116.
- Check for poor connections or loose terminals at ECT sensor 1 and ECT sensor 2.
Are the connections and terminals OK?
YES -Go to step 2.
NO -Repair the connections or terminals, then go to step 27.
- Turn the ignition switch to ON (II).
- Check for Pending or Confirmed DTCs with the HDS.
Are DTC P1116 and P2183 indicated at the same time?
YES -Go to step 15.
NO -Go to step 4.
- Start the engine, and let it idle for 10 minutes.
- Check ECT SENSOR 1 in the DATA LIST with the HDS.
Is about 113°F (45°C) or less indicated?
YES -Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), then go to step 27.
NO -Go to step 6.
- Turn the ignition switch to LOCK (0).
- Drain the coolant (see COOLANT CHECK ).
- Remove ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ).
- Allow ECT sensor 1 to cool to ambient temperature.
- Note the ambient temperature.
- Connect ECT sensor 1 to its 2P connector, but do not install it.
- Turn the ignition switch to ON (II).
- Note the value of ECT SENSOR 1 quickly in the DATA LIST with the HDS.
- Compare the value of ECT SENSOR 1 and the ambient temperature.
Does the value of ECT SENSOR 1 differ 5.4°F (3°C) or more from the ambient temperature?
YES -Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), then go to step 27.
NO -Intermittent failure, the system is OK at this time. Reinstall ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ). Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM.
- Start the engine, and let it idle for 10 minutes.
- Check ECT SENSOR 1 in the DATA LIST with the HDS.
Is about 113°F (45°C) or less Indicated?
YES -Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), then go to step 27.
NO -Go to step 17.
- Let the engine idle 10 minutes.
- Check ECT SENSOR 2 in the DATA LIST with the HDS.
Is about 113°F (45°C) or less indicated?
YES -Replace ECT sensor 2 (see ECT SENSOR 2 REPLACEMENT ), then go to step 27.
NO -Go to step 19.
- Turn the ignition switch to LOCK (0).
- Drain the coolant (see COOLANT CHECK ).
- Remove ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ) and ECT sensor 2 (see ECT SENSOR 2 REPLACEMENT ).
- Allow the sensors to cool to ambient temperature.
- Note the ambient temperature.
- Connect ECT sensor 1 and ECT sensor 2 to their 2P connectors, but do not install them.
- Note the value of ECT SENSOR 1 and ECT SENSOR 2 quickly in the DATA LIST with the HDS.
- Compare the value of ECT SENSOR 1 and the ambient temperature, and the value of ECT SENSOR 2 and the ambient temperature individually.
Does one of the sensors differ more than 5.4°F (3°C) from the ambient temperature?
YES -Replace the sensor that differed more than 5.4°F (3°C) from the ambient temperature. Refill the cooling system (see COOLANT CHECK ), then go to step 27.
NO -Intermittent failure, the system is OK at this time. Reinstall ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ) and ECT sensor 2 (see ECT SENSOR 2 REPLACEMENT ). Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM.
- Turn the ignition switch to ON (II).
- Reset the PCM with the HDS.
- Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1116 indicated?
YES -Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, 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.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.