PCM Power And Ground Circuit Troubleshooting (2017)

PCM Power and Ground Circuit Troubleshooting 

1. Engine starting check

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

   Does the engine start and idle smoothly?

   YES 

   Go to step 2.

   NO 

   Go to step 3.

2. CAN gateway system DTC check

   -1. Check for CAN gateway system DTCs with the HDS.

   DTC Description	DTC
   U0029-00 CAN Gateway F-CAN ch A Bus Off
   U0047-00 CAN Gateway F-CAN ch B Bus Off
   U0056-00 CAN Gateway F-CAN ch C Bus Off
   U0065-00 CAN Gateway F-CAN ch D Bus Off
   U3000-49 CAN Gateway Internal Failure

   DTC (CAN GATEWAY)

   Is DTC U0029-00, U0047-00, U0056-00, U0065-00, and/or U3000-49 indicated?

   YES 

   Go to the indicated DTC's troubleshooting for CAN gateway system. - Refer to: Communication Systems DTC Troubleshooting Index (2014), or Communication Systems DTC Troubleshooting Index (2015), or Communication Systems DTC Troubleshooting Index (2017) ?

   NO 

   Intermittent failure. The system is OK at this time. Check for poor connections or terminals at the PCM.

3. Fuse check 1

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

   - 2. Check the following fuse.

   Fuse	No. A11 (10 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 5.

   NO 

   Go to step 4.

4. Shorted wire check (+B VBU line)

   -1. Remove the blown No. A11 (10 A) fuse from the under-hood fuse/relay box.

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

   - 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
   Test point 1	PCM connector A (50P) No. 7 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short in the +B VBU wire between the PCM (A7) and the No. A11 (10 A) fuse in the under-hood fuse/relay box.

   NO 

   Replace the No. A11 (10 A) fuse and recheck. If the fuse is blown again, replace the PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) . Also replace the No. A11 (10 A) fuse in the under-hood fuse/relay box.

5. Determine possible failure area (+B VBU 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 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)
   Test point 2	Body ground

   Is there battery voltage?

   YES 

   Go to step 6.

   NO 

   Repair an open in the +B VBU wire between the PCM (A7) and the No. A11 (10 A) fuse in the under-hood fuse/relay box.

6. Fuse check 2

   -1. Reconnect PCM connector A (50P).

   - 2. Check the following fuse.

   Fuse	No. A4 (15 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 10.

   NO 

   Go to step 7.

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

   -1. Remove the blown No. A4 (15 A) fuse from the under-hood fuse/relay box.

   - 2. Remove PGM-FI main relay 1.

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

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

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

   Is there continuity?

   YES 

   Repair a short in the +B IGP wire between PGM-FI main relay 1 and the No. A4 (15 A) fuse. If the wire is OK, replace the under-hood fuse/relay box . Also replace the No. A4 (15 A) fuse.

   NO 

   Go to step 8.

8. Part(s) internal circuit check (short in FI MAIN RLY OUT line)

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

   - 2. 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
   • Each injector 2P connector
   • PCM connector A (50P)

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

   Courtesy 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 - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) , then recheck. If the symptom/indication goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) . Also replace the No. A4 (15 A) fuse in the under-hood fuse/relay box.

   NO 

   Go to step 9.

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

   -1. Disconnect the following parts:

   • PGM-FI main relay 2 - Refer to: Relay and Control Unit Locations (2014), or Relay and Control Unit Locations (2015), or Relay and Control Unit Locations (2017)
   • Injectors
   • PCM connector A (50P)

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

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

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

   Is there continuity?

   YES 

   Repair a short in the FI MAIN RLY OUT wire between PGM-FI main relay 1 and each part. Also replace the No. A4 (15 A) fuse in the under-hood fuse/relay box.

   NO 

   The FI MAIN RLY OUT wire is OK. Replace PGM-FI main relay 1. Also replace the No. A4 (15 A) fuse in the under-hood fuse/relay box.

10. Fuse check 3

    -1. Check the following fuse.

    Fuse	No. B9 (20 A)
    Location	Under-dash fuse/relay box

    Is the fuse OK?

    YES 

    Go to step 15.

    NO 

    Go to step 11.

11. Relay check

    -1. Remove the blown No. B9 (20 A) fuse from the under-dash fuse/relay box.

    - 2. Remove PGM-FI main relay 2.

    - 3. Test PGM-FI main relay 2.

    Is the relay OK?

    YES 

    Go to step 12.

    NO 

    Replace PGM-FI main relay 2. Also replace the No. B9 (20 A) fuse in the under-dash fuse/relay box.

12. Determine possible failure area (IG1 FUEL PUMP line, others)

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

    Test condition	Vehicle OFF (LOCK) mode
    	PGM-FI main relay 2: disconnected
    Test point 1	Auxiliary under-hood relay box B 17P socket No. 2
    Test point 2	Body ground

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

    Is there continuity?

    YES 

    Go to step 13.

    NO 

    Go to step 14.

13. Shorted wire check (IG1 FUEL PUMP line)

    -1. Disconnect the following connector.

    Under-dash fuse/relay box connector E (36P)

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

    Test condition	Vehicle OFF (LOCK) mode
    	PGM-FI main relay 2: disconnected
    	Under-dash fuse/relay box connector E (36P): disconnected
    Test point 1	Auxiliary under-hood relay box B 17P socket No. 2
    Test point 2	Body ground

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

    Is there continuity?

    YES 

    Repair a short in the IG1 FUEL PUMP wire between the under-dash fuse/relay box and PGM-FI main relay 2. Also replace the No. B9 (20 A) fuse in the under-dash fuse/relay box.

    NO 

    The IG1 FUEL PUMP wire is OK. Replace the under-dash fuse/relay box . Also replace the No. B9 (20 A) fuse in the under-dash fuse/relay box.

14. Shorted wire check (FUEL PUMP RLY OUT line)

    -1. Disconnect the following connector.

    Fuel tank unit 4P connector

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

    Test condition	Vehicle OFF (LOCK) mode
    	PGM-FI main relay 2: disconnected
    	Fuel tank unit 4P connector: disconnected
    Test point 1	Auxiliary under-hood relay box B 17P socket No. 1
    Test point 2	Body ground

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

    Is there continuity?

    YES 

    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. B9 (20 A) fuse in the under-dash fuse/relay box.

    NO 

    The FUEL PUMP RLY OUT wire is OK. Check the fuel pump, and replace it if needed. Also replace the No. B9 (20 A) fuse in the under-dash fuse/relay box.

15. Open wire check (IG1 FUEL PUMP line)

    -1. Remove PGM-FI main relay 2.

    - 2. Turn the vehicle to the ON mode.

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

    Test condition	Vehicle ON mode
    	PGM-FI main relay 2: disconnected
    Test point 1	Auxiliary under-hood relay box B 17P socket No. 2
    Test point 2	Body ground

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

    Is there battery voltage?

    YES 

    Go to step 16.

    NO 

    Repair an open in the IG1 FUEL PUMP wire between the No. B9 (20 A) fuse and PGM-FI main relay 2.

16. Fuse check 4

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

    - 2. Check the following fuse.

    Fuse	No. D1 (7.5 A)
    Location	Auxiliary under-dash fuse holder

    Is the fuse OK?

    YES 

    Go to step 18.

    NO 

    Go to step 17.

17. Shorted wire check (IG1(F/P)/IG1 MON line)

    -1. Remove the blown No. D1 (7.5 A) fuse from the auxiliary under-dash fuse holder.

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

    - 3. Disconnect the following connector.

    PCM connector E (80P)

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    Test point 1	PCM connector E (80P) No. 36 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)
    Test point 2	Body ground

    Is there continuity?

    YES 

    Repair a short in the IG1(F/P)/IG1 MON wire between the PCM (E36) and the No. D1 (7.5 A) fuse. Also replace the No. D1 (7.5 A) fuse.

    NO 

    Replace the No. D1 (7.5 A) fuse and recheck. If the fuse is blown again, replace the PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) . Also replace the No. D1 (7.5 A) fuse in the auxiliary under-dash fuse holder.

18. Open wire check (IG1(F/P)/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. Turn the vehicle to the ON mode.

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

    Test condition	Vehicle ON mode
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    Test point 1	PCM connector E (80P) No. 36 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)
    Test point 2	Body ground

    Is there battery voltage?

    YES 

    Go to step 19.

    NO 

    Repair an open in the IG1(F/P)/IG1 MON wire between the PCM (E36) and the No. D1 (7.5 A) fuse.

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

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

    - 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
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    Test point 1	PCM connector A (50P) No. 5 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)
    Test point 2	Body ground

    Is there battery voltage?

    YES 

    Go to step 22.

    NO 

    Go to step 20.

20. Open wire check (+B IGP line) 1

    -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
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    	PGM-FI main relay 1: disconnected
    Test point 1	PGM-FI main relay 1 4P socket No. 3
    Test point 2	Body ground

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

    Is there battery voltage?

    YES 

    Go to step 21.

    NO 

    Repair an open in the +B IGP wire between PGM-FI main relay 1 and the No. A4 (15 A) fuse. If the wire is OK, replace the under-hood fuse/relay box .

21. 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
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    	PGM-FI main relay 1: disconnected
    Test point 1	PGM-FI main relay 1 4P socket No. 4
    Test point 2	PCM connector A (50P) No. 5 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)

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

    Is there continuity?

    YES 

    The FI MAIN RLY CL- wire is OK. Test PGM-FI main relay 1 . If the relay is OK, check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) , then recheck. If the symptom/indication goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) .

    NO 

    Repair an open in the FI MAIN RLY CL- wire between the PCM (A5) and PGM-FI main relay 1.

22. Open wire check (+B IGP line) 2

    -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
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    	PGM-FI main relay 1: disconnected
    Test point 1	PGM-FI main relay 1 4P socket No. 1
    Test point 2	Body ground

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

    Is there battery voltage?

    YES 

    Go to step 23.

    NO 

    Repair an open in the +B IGP wire between PGM-FI main relay 1 and the No. A4 (15 A) fuse. If the wire is OK, replace the under-hood fuse/relay box .

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

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

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (50P): disconnected
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    	PGM-FI main relay 1: disconnected
    Test point 1	PGM-FI main relay 1 4P socket No. 2
    Test point 2	PCM connector A (50P) No. 8 - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)

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

    Is there continuity?

    YES 

    Go to step 24.

    NO 

    Repair an open in the FI MAIN RLY OUT wire between the PCM (A8) and PGM-FI main relay 1.

24. Relay check

    -1. Test PGM-FI main relay 1.

    Is the relay OK?

    YES 

    Go to step 25.

    NO 

    Replace PGM-FI main relay 1.

25. Open wire check (GND, GND 1, GND 3, PGM, LG lines)

    -1. Check for continuity between the following test points and body ground individually.

    Test condition	Vehicle OFF (LOCK) mode
    	PCM connector A (50P): disconnected
    	PCM connector E (80P): disconnected
    	PGM-FI main relay 2: disconnected
    	PGM-FI main relay 1: disconnected

    Connector	Terminal
    PCM connector A (50P) - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)	No. 13
    PCM connector E (80P) - Refer to: PCM Connector for Inputs and Outputs (2014 2015),  or PCM Connector for Inputs and Outputs (2017)	No. 7
    	No. 22
    	No. 23
    	No. 24

    Is there continuity?

    YES 

    The GND, GND 1, GND 3, PGM, and LG wires are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) , then recheck. If the symptom/indication goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (2014 2015),  or PCM Removal and Installation (2017) .

    NO 

    Repair an open in the wire between the PCM (A13, E7, E22, E23, E24) and G101.