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DTC P04C1

DTC P04C1  : Fuel Fill Door Open Relay Control Circuit Low Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P04C1 Fuel Fill Door Open Relay Control Circuit Low Voltage    

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. Operate the fuel fill door opener switch to open the fuel fill door, and wait a few seconds.

    -6. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P04C1 Fuel Fill Door Open Relay Control Circuit Low Voltage    

    DTC (PGM-FI)

    Is DTC P04C1 indicated?

    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 the fuel fill door opener solenoid relay 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.

  2. Fuse check

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

    -2. Check the No. B11 fuse .

    Is the fuse OK?

    YES 

    Go to step 3.

    NO 

    Replace the No. B11 fuse. Also check for short to ground on the No. B11 fuse circuit if needed.

  3. Relay check

    -1. Remove the fuel fill door opener solenoid relay .

    -2. Test the fuel fill door opener solenoid relay .

    Is the fuel fill door opener solenoid relay OK?

    YES 

    The fuel fill door opener solenoid relay is OK. Go to step 4.

    NO 

    Replace the fuel fill door opener solenoid relay.

  4. Open wire check (DBW RLY OUT line)

    -1. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      Fuel fill door opener solenoid relay: disconnected
    Test point 1 Fuel fill door opener solenoid relay 4P socket (female terminals) No. 3:
    Test point 2 Body ground
    GHH385134Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The DBW RLY OUT wire is OK. Go to step 5.

    NO 

    Repair an open in the DBW RLY OUT wire between the under-hood fuse/relay box and the fuel fill door opener solenoid relay.

  5. Open wire check (FUEL LID ACT RLY CL- line)

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

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

    -3. Disconnect the following connector.

    PCM connector A (50P)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      Fuel fill door opener solenoid relay: disconnected
    Test point 1 PCM connector A (50P) No. 23
    Test point 2 Fuel fill door opener solenoid relay 4P socket (female terminals) No. 4:
    GHH385136Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The FUEL LID ACT RLY CL- wire is OK. Go to step 6.

    NO 

    Repair an open in the FUEL LID ACT RLY CL- wire between the PCM (A23) and the fuel fill door opener solenoid relay.

  6. Shorted wire check (FUEL LID ACT RLY CL- line)

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

    Test condition Vehicle OFF (LOCK) mode
      Fuel fill door opener solenoid relay: disconnected
      PCM connector A (50P): disconnected
    Test point 1 PCM connector A (50P) No. 23
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short in the FUEL LID ACT RLY CL- wire between the PCM (A23) and the fuel fill door opener solenoid relay.

    NO 

    The FUEL LID ACT RLY CL- wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .