DTC P0117 (19-21 9-Speed A/T)

DTC P0117  : Engine Coolant Temperature (ECT) Sensor 1 Circuit Low Voltage

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   - 2. Check the parameter (s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   ECT SENSOR 1	Less than 0.08	V

   Do the current condition (s) match the threshold?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems

2. ECT sensor 1 performance check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Disconnect the following connector.

   ECT sensor 1 2P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Check the parameter (s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   ECT SENSOR 1	Less than 0.08	V

   Do the current condition (s) match the threshold?

   YES 

   Go to step 3.

   NO 

   Replace ECT sensor 1 - Refer to: ECT Sensor 1 Removal and Installation .

3. Shorted wire check (TW line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Jump the SCS line with the HDS, and wait more than 1 minute.

   - 3. Disconnect the following connector.

   PCM connector E (80P)

   - 4. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	ECT sensor 1 2P connector: disconnected
   	PCM connector E (80P): disconnected
   Test point 1	ECT sensor 1 2P connector (female terminals) No. 2:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   Repair a short in the TW wire between the PCM (E38) and ECT sensor 1.

   NO 

   The TW wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (9-Speed A/T 2019 2020 2021) , then recheck. If DTC P0117 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (9-Speed A/T 2019 2020 2021) .