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Home >> Honda >> 2021 >> Clarity Plug-In Hybrid >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC Diagnostics (P0221 - P0563) (Plug-In) >> DTC Troubleshooting >> DTC P0451
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DTC P0451

DTC P0451  : FTP Sensor Circuit Range/Performance Problem

NOTE:
  • Before you troubleshoot, review the general troubleshooting information .
  • If DTC P2451 is stored at the same time as DTC P0451, troubleshoot DTC P2451 first, then recheck for DTC P0451.
  • If DTC P0497 and P2451 are stored at the same time as DTC P0451, troubleshoot DTC P0497 first, then recheck for DTC P0451.
DTC Description Confirmed DTC Pending DTC
P0451 FTP Sensor Circuit Range/Performance Problem    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode.

    -4. Turn the vehicle to the ON mode.

    -5. Select the EVAP TEST in the Function Test Menu, then select the EVAP Leak Check Module Test with the HDS.

    EVAP TEST

    Is the result OK?

    YES 

    If the test result is PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the FTP sensor 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.

    NO 

    Go to step 2

  2. FTP sensor installation check

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

    -2. Remove the FTP sensor , and check the installation of the FTP sensor, also check for the blockage in the FTP sensor port and hose.

    Is it OK?

    YES 

    Replace the FTP sensor .

    NO 

    Install the FTP sensor correctly , or remove the blockage in the port or hose.