DTC P0657

DTC P0657  : PCM Power Supply Circuit Malfunction

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

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 PGM-FI main relay 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 .

2. Relay check

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

   -2. Remove PGM-FI main relay 1 .

   -3. Test PGM-FI main relay 1 .

   Is the relay OK?

   YES 

   Go to step 3.

   NO 

   Replace PGM-FI main relay 1.

3. Fuse check

   -1. Check the following fuse.

   Fuse	No. B9 (15 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 7.

   NO 

   Go to step 4.

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

   -1. Remove the blown No. B9 (15 A) fuse from the under-hood fuse/relay box.

   -2. Check for continuity the between following test points and body ground individually.

   Test condition	Vehicle OFF (LOCK) mode
   	PGM-FI main relay 1: disconnected
   Test point 1	PGM-FI main relay 1 4P socket (female terminals) No. 1 and No. 3:
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   Repair a short in the +B MAIN RLY wire between the No. B9 (15 A) fuse in the under-hood fuse/relay box and PGM-FI main relay 1. Also replace the No. B9 (15 A) 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.

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

   • PCM connector A (50P)
   • ETCS control relay
   • CMP sensor 3P connector
   • CKP sensor 3P connector
   • Power distribution module connector A (18P)

   Test condition	Vehicle OFF (LOCK) mode
   	PGM-FI main relay 1: disconnected
   Test point 1	PGM-FI main relay 1 4P socket (female terminals) No. 2:
   Test point 2	Body ground

   Courtesy 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 , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM . Also replace the No. B9 (15 A) fuse.

   NO 

   Go to step 6.

6. Shorted wire check (IGP1/IGP line)

   -1. Disconnect the following parts and connectors.

   PCM connector A (50P)

   ETCS control relay

   CMP sensor 3P connector

   CKP sensor 3P connector

   Power distribution module connector A (18P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	PGM-FI main relay 1: disconnected
   	PCM connector A (50P): disconnected
   	ETCS control relay: disconnected
   	CMP sensor 3P connector: disconnected
   	CKP sensor 3P connector: disconnected
   	Power distribution module connector A (18P): disconnected
   Test point 1	PCM connector A (50P) No. 4
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short in the IGP1/IGP line between the PCM (A4), PGM-FI main relay 1, the ETCS control relay, the CMP sensor, the CKP sensor, and the power distribution module. If the wire is OK, check for a short in the IGP1 wire between the PCM (A4) and the No. B27 (5 A) fuse in the under-hood fuse/relay box and repair it if needed. Also replace the No. B9 (15 A) fuse in the under-hood fuse/relay box.

   NO 

   Replace PGM-FI main relay 1. Also replace the No. B9 (15 A) fuse in the under-hood fuse/relay box.

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

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

   -2. Install PGM-FI main relay 1 .

   -3. Jump the SCS line with the HDS, and wait more than 1 minute.

   -4. Disconnect the following connector.

   PCM connector A (50P)

   -5. 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. 22
   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 MAIN RLY line, others)

   -1. Remove PGM-FI main relay 1 .

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (50P): disconnected
   	PGM-FI main relay 1: disconnected
   Test point 1	PGM-FI main relay 1 4P socket (female terminals) No. 3:
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   Go to step 9.

   NO 

   Repair an open in the +B MAIN RLY wire between the No. B9 (15 A) fuse in the under-hood fuse/relay box and PGM-FI main relay 1.

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

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (50P): disconnected
   	PGM-FI main relay 1: disconnected
   Test point 1	PGM-FI main relay 1 4P socket (female terminals) No. 4:
   Test point 2	PCM connector A (50P) No. 22

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

   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 , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM .

   NO 

   Repair an open in the FI MAIN RLY CL- wire between the PCM (A22) and PGM-FI main relay 1.

10. Open wire check (IGP1 line)

    -1. Remove PGM-FI main relay 1 .

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (50P): disconnected
    	PGM-FI main relay 1: disconnected
    Test point 1	PGM-FI main relay 1 4P socket (female terminals) No. 2:
    Test point 2	PCM connector A (50P) No. 4

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

    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 , then recheck. If DTC P0657 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the IGP1 wire between the PCM (A4) and PGM-FI main relay 1.