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DTC P0115: ECT Sensor 1 Out of Range (L4) (2018-19)

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems (L4), or How to Troubleshoot the Dual Clutch Transmission (DCT), or How to Troubleshoot the Brake Booster Pressure Monitoring System (With Auto Idle Stop System), .

DTC Description Confirmed DTC Pending DTC
P0115 ECT Sensor 1 Out of Range    

DTC (PGM-FI)

  1. Problem verification 1

    -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 0.09 V    

    Do the current condition (s) match the threshold?

    YES 

    The failure is duplicated. Go to step 3.

    NO 

    Go to step 2.

  2. Problem verification 2

    -1. Check the parameter (s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    ECT SENSOR 1 More than 4.99 V    

    Do the current condition (s) match the threshold?

    YES 

    The failure is duplicated. Go to step 5. Refer to:  5

    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 (L4), or How to Troubleshoot the Dual Clutch Transmission (DCT), or How to Troubleshoot the Brake Booster Pressure Monitoring System (With Auto Idle Stop System), .

  3. Determine possible failure area (ECT sensor 1, others)

    -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 0.09 V    

    Do the current condition (s) match the threshold?

    YES 

    Go to step 4.

    NO 

    Replace ECT sensor 1 - Refer to: ECT Sensor 2 Removal and Installation, or ECT Sensor 1 Removal and Installation (L4) .

  4. 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 B (51P)

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

    Test condition Vehicle OFF (LOCK) mode
      ECT sensor 1 2P connector: disconnected
      PCM connector B (51P): disconnected
    Test point 1 ECT sensor 1 2P connector (female terminals) No. 2:
    Test point 2 Body ground
    GHH198321Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the TW wire between the PCM (B25) 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 (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) .

  5. Determine possible failure area (ECT sensor 1, others)

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

    - 2. Disconnect the following connector.

    ECT sensor 1 2P connector

    - 3. Connect terminals A and B with a jumper wire.

    Terminal A ECT sensor 1 2P connector (female terminals) No. 1:
    Terminal B ECT sensor 1 2P connector (female terminals) No. 2:
    GHH198324Courtesy of HONDA, U.S.A., INC.

    - 4. Turn the vehicle to the ON mode.

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

    Signal Threshold Current conditions
    Values Unit Values Unit
    ECT SENSOR 1 More than 4.99 V    

    Do the current condition (s) match the threshold?

    YES 

    Go to step 6.

    NO 

    Replace ECT sensor 1 - Refer to: ECT Sensor 2 Removal and Installation, or ECT Sensor 1 Removal and Installation (L4) .

  6. Determine possible failure area (TW line, others)

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

    - 2. Remove the jumper wire from the ECT sensor 1 2P connector.

    - 3. Turn the vehicle to the ON mode.

    - 4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      ECT sensor 1 2P connector: disconnected
    Test point 1 ECT sensor 1 2P connector (female terminals) No. 2:
    Test point 2 Body ground
    GHH198326Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Go to step 7.

    NO 

    Go to step 8.

  7. Open wire check (SG2 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 B (51P)

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

    Test condition Vehicle OFF (LOCK) mode
      ECT sensor 1 2P connector: disconnected
      PCM connector B (51P): disconnected
    Test point 1 ECT sensor 1 2P connector (female terminals) No. 1:
    Test point 2 PCM connector B (51P) No. 39 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19),
    GHH198328Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The SG2 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 (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) .

    NO 

    Repair an open in the SG2 wire between the PCM (B39) and ECT sensor 1.

  8. Open 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 B (51P)

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

    Test condition Vehicle OFF (LOCK) mode
      ECT sensor 1 2P connector: disconnected
      PCM connector B (51P): disconnected
    Test point 1 ECT sensor 1 2P connector (female terminals) No. 2:
    Test point 2 PCM connector B (51P) No. 25 - Refer to: PCM Connector for Inputs and Outputs (L4) (2015-17) or PCM Connector for Inputs and Outputs (L4) (2018-19),
    GHH198330Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    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 (With SH-AWD), or PCM Removal and Installation (Without SH-AWD) .

    NO 

    Repair an open in the TW wire between the PCM (B25) and ECT sensor 1.

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