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Home >> Honda >> 2021 >> CR-V EX-L, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 7 (Engine Control System / Engine Mechanical - Testing & Troubleshooting (Hybrid)) >> Troubleshooting >> PCM Power and Ground Circuit Troubleshooting

PCM Power and Ground Circuit Troubleshooting

WARNING: This page is about a different variant/trim than selected.

PCM Power and Ground Circuit Troubleshooting 

  1. Engine starting check

    -1. Enter the maintenance mode, then try to start the engine .

    Does the engine start and idle smoothly?

    YES 

    Go to the troubleshooting for CAN gateway system DTC(s) .

    NO 

    Go to step 2.

  2. Fuse check 1

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

    -2. Check the following fuse.

    Fuse No. A12

    Is the fuse OK?

    YES 

    Go to step 3.

    NO 

    Go to step 4.

  3. Determine possible failure area (+B_BACKUP_FI-ECU line, others)

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

    -2. Disconnect the following connector.

    PCM connector A (50P)

    -3. 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. 7 
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Go to step 5.

    NO 

    Repair an open in the +B_BACKUP_FI-ECU wire between PCM (A7) and the No. A12 fuse .

  4. Shorted wire check (+B_BACKUP_FI-ECU line)

    -1. Remove the blown No. A12 fuse .

    -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 resistance 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. 7 
    Test point 2 Body ground

    Is there 1 MΩ or more?

    YES 

    Go to step 5.

    NO 

    Repair a short in the +B_BACKUP_FI-ECU wire between the PCM (A7) and the No. A12 fuse. Also replace the No. A12 fuse.

  5. Fuse check 2

    -1. Check the following fuse.

    Fuse No. A7

    Is the fuse OK?

    YES 

    Go to step 9.

    NO 

    Go to step 6.

  6. Shorted wire check (+B_IGP line)

    -1. Remove the blown No. A7 fuse .

    -2. Disconnect the following connector.

    Relay circuit board connector C (18P)

    -3. Measure the resistance between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      Relay circuit board connector C (18P): disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 18:
    Test point 2 Body ground
    GHH378303Courtesy of HONDA, U.S.A., INC.

    Is there 1 MΩ or more?

    YES 

    Go to step 7.

    NO 

    Repair a short in the +B_IGP wire between the No. A7 fuse and the relay circuit board. If the wire is OK, replace the under-hood fuse/relay box . Also replace the No. A7 fuse.

  7. Part(s) internal circuit check (short in FI_MAIN_RLY_OUT line):

    Disconnect each of the parts or connectors below, one at a time, then check for continuity between test points 1 and 2.

    • PGM-FI main relay 2
    • PCM connector A (50P)
    • Each injector 2P connector
    Test condition Vehicle OFF (LOCK) mode
    Relay circuit board connector C (18P): disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 17:
    Test point 2 Body ground
    GHH378305Courtesy of HONDA, U.S.A., INC.

    Does continuity go away when one of the above components is disconnected?

    YES 

    Replace the part that made the short to body ground go away when it was disconnected. If the part is the 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. A7 fuse .

    NO 

    Parts are OK. Go to step 8.

  8. Shorted wire check (FI_MAIN_RLY_OUT line):

    Disconnect the following parts or connectors:

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

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

    Test condition Vehicle OFF (LOCK) mode
      Relay circuit board connector C (18P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector A (50P): disconnected
      Each injector 2P connector: disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 17:
    Test point 2 Body ground
    GHH378307Courtesy of HONDA, U.S.A., INC.

    Is there 1 MΩ or more?

    YES 

    The FI_MAIN_RLY_OUT wire is OK. Replace the relay circuit board . Also replace the No. A7 fuse .

    NO 

    Repair a short in the FI_MAIN_RLY_OUT wire between the relay circuit board and each part. Also replace the No. A7 fuse.

  9. Fuse check 3

    -1. Check the following fuse.

    Fuse No. D8

    Is the fuse OK?

    YES 

    Go to step 14.

    NO 

    Go to step 10.

  10. Relay check

    -1. Remove PGM-FI main relay 2 .

    -2. Test PGM-FI main relay 2 .

    Is the relay OK?

    YES 

    PGM-FI main relay 2 is OK. Go to step 11.

    NO 

    Replace PGM-FI main relay 2. Also replace the No. D8 fuse .

  11. Determine possible failure area (IG1_FUEL_PUMP line, others)

    -1. Remove the blown No. D8 fuse .

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
    Test point 1 PGM-FI main relay 2 4P socket (female terminals) No. 1:
    Test point 2 Body ground
    GHH378309Courtesy of HONDA, U.S.A., INC.

    Is there 1 MΩ or more?

    YES 

    Go to step 13.

    NO 

    Go to step 12.

  12. Shorted wire check (IG1_FUEL_PUMP line)

    -1. Disconnect the following connector.

    Under-dash fuse/relay box connector C (27P)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      Under-dash fuse/relay box connector C (27P): disconnected
    Test point 1 PGM-FI main relay 2 4P socket (female terminals) No. 1:
    Test point 2 Body ground
    GHH378311Courtesy of HONDA, U.S.A., INC.

    Is there 1 MΩ or more?

    YES 

    The IG1_FUEL_PUMP wire is OK. Replace the No. D8 fuse . If the fuse blown again, replace the under-dash fuse/relay box .

    NO 

    Repair a short in the IG1_FUEL_PUMP wire between PGM-FI main relay 2 and the No. D8 fuse. Also replace the No. D8 fuse.

  13. Shorted wire check (FUEL_PUMP_RLY_OUT line)

    -1. Disconnect the following connector.

    Fuel tank unit 4P connector

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      Fuel tank unit 4P connector: disconnected
    Test point 1 Fuel tank unit 4P connector (female terminals) No. 1:
    Test point 2 Body ground
    GHH378313Courtesy of HONDA, U.S.A., INC.

    Is there 1 MΩ or more?

    YES 

    The FUEL_PUMP_RLY_OUT wire is OK. Check the fuel pump, and replace it if needed. Also replace the No. D8 fuse .

    NO 

    Repair a short in the FUEL_PUMP_RLY_OUT wire between PGM-FI main relay 2 and the fuel tank unit. Also replace the No. D8 fuse.

  14. Open wire check (IG1_FUEL_PUMP line)

    -1. Remove PGM-FI main relay 2 .

    -2. Exit the SCS mode with the HDS.

    -3. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
    Test point 1 PGM-FI main relay 2 4P socket (female terminals) No. 1:
    Test point 2 Body ground
    GHH378315Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The IG1_FUEL_PUMP wire is OK. Go to step 15.

    NO 

    Repair an open in the IG1_FUEL_PUMP wire between the No. D8 fuse and PGM-FI main relay 2.

  15. Fuse check 4

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

    -2. Check the following fuse.

    Fuse No. D11

    Is the fuse OK?

    YES 

    Go to step 17.

    NO 

    Go to step 16.

  16. Shorted wire check (IG1 (MONI)/IG1_MON line)

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

    -2. Disconnect the following connector.

    PCM connector E (80P)

    -3. Measure the resistance between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector E (80P): disconnected
    Test point 1 PCM connector E (80P) No. 36 
    Test point 2 Body ground

    Is there 1 MΩ or more?

    YES 

    The IG1 (MONI)/IG1_MON wire is not shorted. Go to step 18.

    NO 

    Repair a short in the IG1 (MONI)/IG1_MON wire between the PCM (E36) and the No. D11 fuse . Also replace the No. D11 fuse.

  17. Open wire check (IG1 (MONI)/IG1_MON line)

    -1. Reinstall the No. D11 fuse .

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

    -3. Disconnect the following connector.

    PCM connector E (80P)

    -4. Turn the vehicle to the ON mode.

    -5. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector E (80P): disconnected
    Test point 1 PCM connector E (80P) No. 36 
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    The IG1 (MONI)/IG1_MON wire is OK. Go to step 18.

    NO 

    Repair an open in the IG1 (MONI)/IG1_MON wire between the PCM (E36) and the No. D11 fuse.

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

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

    -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 2: disconnected
      PCM connector E (80P): disconnected
    Test point 1 PCM connector A (50P) No. 5 
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Go to step 21.

    NO 

    Go to step 19.

  19. Open wire check (+B_IGP line)

    -1. Disconnect the following connector.

    Relay circuit board connector C (18P)

    -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 2: disconnected
      PCM connector E (80P): disconnected
      Relay circuit board connector C (18P): disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 18:
    Test point 2 Body ground
    GHH378317Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 20.

    NO 

    Repair an open in the +B_IGP wire between the relay circuit board and the No. A7 fuse .

  20. Open wire check (FI_MAIN_RLY_CL- line)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector E (80P): disconnected
      Relay circuit board connector C (18P): disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 5:
    Test point 2 PCM connector A (50P) No. 5 
    GHH378319Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The FI_MAIN_RLY_CL- wire is OK. Remove and test the relay circuit board . If the relay circuit board is OK, 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.

  21. Open wire check (FI_MAIN_RLY_OUT line)

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

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector E (80P): disconnected
      Relay circuit board connector C (18P): disconnected
    Test point 1 Relay circuit board connector C (18P) (female terminals) No. 17:
    Test point 2 PCM connector A (50P) No. 8 
    GHH378321Courtesy of HONDA, U.S.A., INC.

    Is there 1.0 Ω or less?

    YES 

    The FI_MAIN_RLY_OUT wire is OK. Go to step 22.

    NO 

    Repair an open in the FI_MAIN_RLY_OUT wire between the PCM (A8) and the relay circuit board.

  22. Relay circuit board check

    -1. Remove and test the relay circuit board .

    Is the relay circuit board OK?

    YES 

    The relay circuit board is OK. Go to step 23.

    NO 

    Replace the relay circuit board .

  23. Open wire check (GND lines)

    -1. Measure the resistance between the following test points and body ground individually.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      PGM-FI main relay 2: disconnected
      PCM connector E (80P): disconnected
      Relay circuit board: removed
    Connector Terminal
    PCM connector A (50P)  No. 13
    Connector Terminal
    PCM connector E (80P)  No. 22
    No. 23
    No. 24

    Is there 1.0 Ω or less?

    YES 

    The FI_ECU_GND wire, the GND_2 wire, the GND_3 wire, and the GND_4 wire are OK. 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 ECU GND wire, the GND_2 wire, the GND_3 wire, and/or the GND_4 wire between the PCM (A13, E22, E23, E24) and G101.

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