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DTC P0657 (1.5 L Engine)

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DTC P0657  : PCM Power Supply Circuit Malfunction

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC Description Confirmed DTC Pending DTC
P0657 PCM Power Supply Circuit Malfunction    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Start the engine.

    -4. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P0657 PCM Power Supply Circuit Malfunction    

    Is DTC P0657 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 relay circuit board 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. Relay circuit board check

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

    -2. Remove and test the relay circuit board .

    Is the relay circuit board OK?

    YES 

    Go to step 3.

    NO 

    Replace the relay circuit board .

  3. Fuse check

    -1. Check the following fuse.

    Fuse No. A13

    Is the fuse OK?

    YES 

    Go to step 7.

    NO 

    Go to step 4.

  4. Determine possible failure area (+B IGP line, others)

    -1. Remove the blown No. A13 fuse .

    -2. Remove the injector relay .

    -3. Check for continuity the between following test points and body ground individually.

    Test condition Vehicle OFF (LOCK) mode
    Relay circuit board: disconnected
    Injector relay: disconnected
    Test point 1 Relay circuit board connector C (22P) (female terminals) No. 11:
    Test point 2 Body ground
    GHH393425Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the +B IGP wire between the No. A13 fuse, the relay circuit board, and the injector relay. Also replace the No. A13 fuse.

    NO 

    Go to step 5.

  5. Parts internal circuit check

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

    Check for continuity between test points 1 and 2 while disconnecting these parts, one at a time:

    • PGM-FI main relay 2
    • PCM connector A (50P)
    Test condition Vehicle OFF (LOCK) mode
      Relay circuit board: disconnected
    Test point 1 Relay circuit board connector C (22P) (female terminals) No. 10:
    Test point 2 Body ground
    GHH393427Courtesy of HONDA, U.S.A., INC.

    Does continuity go away with the part (s) removed?

    YES 

    Replace the part that continuity goes away when it was disconnected. If the part is PCM, Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM . Also replace the No. A13 fuse .

    NO 

    Go to step 6.

  6. Shorted wire check (FI MAIN RLY OUT line)

    -1. Disconnect the following connectors.

    PGM-FI main relay 2
    PCM connector A (50P)

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

    Test condition Vehicle OFF (LOCK) mode
      Relay circuit board: disconnected
      PGM-FI main relay 2: disconnected
      PCM connector A (50P): disconnected
    Test point 1 PCM connector A (50P) No. 8
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short in the FI MAIN RLY OUT line between the relay circuit board, PGM-FI main relay 2, and the PCM (A8). Also replace the No. A13 fuse .

    NO 

    Replace the relay circuit board . Also replace the No. A13 fuse .

  7. Determine possible failure area (PGM-FI main relay 1 control circuit, others)

    -1. Install the relay circuit board .

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

    -3. Disconnect the following connector.

    PCM connector A (50P)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
    Test point 1 PCM connector A (50P) No. 5
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Go to step 10.

    NO 

    Go to step 8.

  8. Determine possible failure area (+B IGP line, others)

    -1. Disconnect the following connector.

    Relay circuit board connector C (22P)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      Relay circuit board connector C (22P): disconnected
    Test point 1 Relay circuit board connector C (22P) (female terminals) No. 11:
    Test point 2 Body ground
    GHH393429Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 9.

    NO 

    Repair an open in the +B IGP wire between the No. A13 fuse and the relay circuit board.

  9. Open wire check (FI MAIN RLY CL- line)

    -1. Connect terminals A and B with a jumper wire.

    Terminal A Relay circuit board connector C (22P) (female terminals) No. 13:
    Terminal B Body ground
    GHH393431Courtesy of HONDA, U.S.A., INC.

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      Relay circuit board connector C (22P): disconnected
      Relay circuit board connector C (22P) No. 13: jumped to body ground
    Test point 1 PCM connector A (50P) No. 5
    Test point 2 Body ground

    Is there continuity?

    YES 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .

    NO 

    Repair an open in the FI MAIN RLY CL- wire between the PCM (A5) and the relay circuit board.

  10. Open wire check (FI MAIN RLY OUT line)

    -1. Disconnect the following connector.

    Relay circuit board connector C (22P)

    -2. Connect terminals A and B with a jumper wire.

    Terminal A Relay circuit board connector C (22P) (female terminals) No. 10:
    Terminal B Body ground
    GHH393433Courtesy of HONDA, U.S.A., INC.

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      Relay circuit board connector C (22P): disconnected
      Relay circuit board connector C (22P) No. 10: jumped to body ground
    Test point 1 PCM connector A (50P) No. 8
    Test point 2 Body ground

    Is there continuity?

    YES 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .

    NO 

    Repair an open in the FI MAIN RLY OUT wire between the PCM (A8) and the relay circuit board.

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