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DLC Circuit Troubleshooting

NOTE: If you suspect the HDS or the HDS DLC cable may be the source of the communication problem, verify that they are working properly by connecting them to a known-good, like vehicle and system, and checking for communication problems.
  1. Turn the ignition switch to LOCK (0).
  2. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
    NOTE: Make sure the HDS is properly connected to the DLC.
  3. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Go to step 4.

    NO  -Go to step  25.

  4. Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.

    Are any Pending or Confirmed DTCs indicated? 

    YES  -Go to the indicated DTC'S TROUBLESHOOTING .

    NO  -

    • If the HDS does not communicate with the SRS, go to step 5.
    • If the HDS does not communicate with the VSA system, go to step  7.
    • If the HDS does not communicate with the TPMS, go to step  9.
    • If the HDS does not communicate with the SH-AWD system, go to step  11.
    • If the HDS does not communicate with the ACC system, go to step  13.
    • If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step  15.
    • If the HDS does not communicate with the BODY ELECTRICAL system, go to step  17.
  5. Turn the ignition switch to LOCK (0).
  6. Turn the ignition switch to ON (II), and watch the SRS indicator.

    Does the SRS indicator come on and go off? 

    YES  -Go to step  19.

    NO  -Go to the SRS general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

  7. Turn the ignition switch to LOCK (0).
  8. Turn the ignition switch to ON (II), and watch the VSA indicator.

    Does the VSA indicator come on and go off? 

    YES  -Go to step  19.

    NO  -Go to the VSA system symptom troubleshooting for ABS indicator, brake system indicator, or VSA indicator do not go off (see ABS INDICATOR, BRAKE SYSTEM INDICATOR, AND VSA INDICATOR DO NOT GO OFF ).

  9. Turn the ignition switch to LOCK (0).
  10. Turn the ignition switch to ON (II), and watch the TPMS indicator.

    Does the TPMS indicator come on and go off? 

    YES  -Go to step  19.

    NO  -Go to the TPMS symptom troubleshooting for TPMS indicator does not go off, and no DTCs are stored (see GENERAL TROUBLESHOOTING INFORMATION ).

  11. Turn the ignition switch to LOCK (0).
  12. Turn the ignition switch to ON (II), and watch the SH-AWD indicator.

    Does the SH-AWD indicator come on and go off? 

    YES  -Go to step  19.

    NO  -Go to the SH-AWD system symptom troubleshooting for SH-AWD indicator does not go off, and no DTCs are stored (see GENERAL TROUBLESHOOTING INFORMATION ).

  13. Turn the ignition switch to LOCK (0).
  14. Turn the ignition switch to ON (II), and watch the ACC indicator.

    Does the ACC indicator come on and go off? 

    YES  -Go to step  19.

    NO  -Go to the ACC general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

  15. Turn the ignition switch to LOCK (0).
  16. Turn the ignition switch to ON (II), and watch the immobilizer indicator.

    Does the immobilizer indicator stay on or flash? 

    YES  -Go to the immobilizer system's troubleshooting (see SYSTEM DESCRIPTION ).

    NO  -Go to step  19.

  17. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
  18. Check the gauge display.

    Is Error 2 indicated? 

    YES  -Check for B-CAN system DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  -Go to step 19.

  19. Turn the ignition switch to LOCK (0), then do the battery terminal disconnection procedure (see BATTERY TERMINAL DISCONNECTION AND RECONNECTION ), and wait at least 3 minutes before continuing.
  20. Disconnect the HDS from the DLC.
  21. Check for continuity between body ground and DLC terminals No. 1 and No. 7 individually.
    Fig 1: Checking Continuity Between Body Ground And Dlc Terminals No. 1 And No. 7
    G07362035Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 22.

    NO  -Go to step  23.

  22. Continue to check for continuity between body ground and DLC terminals No. 1 and No. 7 individually, while disconnecting these connectors, one at a time:
    • SRS unit connector A (28P)
    • VSA modulator-control unit 36P connector
    • TPMS control unit connector B (20P)
    • Immobilizer control unit-receiver 7P connector
    • SH-AWD control unit connector A (26P)
    • ACC (adaptive cruise control) unit 20P connector
    • Driver's under-dash fuse/relay box connector P (30P)
    • Keyless access control unit connector A (31P)

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

      YES  -Replace the part that caused continuity go away when it was disconnected.

      NO  -Repair a short in the wire between DLC terminal No. 7 (K-LINE) and the VSA modulator-control unit, the SRS unit, the TPMS control unit, the immobilizer control unit-receiver, the SH-AWD control unit, the ACC unit, and the driver's under-dash fuse/relay box, or between DLC terminal No. 1 (DIAG-H line) and the immobilizer control unit-receiver, or the keyless access control unit.

  23. Connect DLC terminals No. 1 and No. 7 to body ground with jumper wires.
    Fig 2: Connecting Dlc Terminals No. 1 And No. 7 To Body Ground With Jumper Wires
    G07362036Courtesy of AMERICAN HONDA MOTOR CO., INC.
  24. Check for continuity between body ground and the following connector terminals:
    CONTINUITY SPECIFICATIONS

    Connector Terminal
    SRS unit A(28P) No. 24 (RED)
    VSA modulator-control unit 36P No. 3(BLU)
    TPMS control unit B (20P) No. 9 (LT BLU)
    Immobilizer control unit-receiver 7P No. 3 (GRY)
    SH-AWD control unit A (26P) No. 15 (LT BLU)
    ACC unit 20P No. 8 (BLU)
    Driver's under-dash fuse/relay box connector P (30P) No. 6 (RED)
    Keyless access control unit A (31P) No. 6 (GRY)

    Is there continuity between body ground and each of the terminals in the chart? 

    YES  -Replace the part that does not communicate with the HDS.

    NO  -Repair an open in the wire between the DLC (K-LINE and DIAG-H lines) and the appropriate connector.

  25. Check for B-CAN system DTCs without the HDS (see GENERAL TROUBLESHOOTING INFORMATION ).

    Is DTC U0029 and/or U0100 indicated? 

    YES  -Go to step  37.

    NO  -Go to step 26.

  26. Turn the ignition switch to LOCK (0).
  27. Disconnect the HDS from the DLC.
  28. Measure the voltage between DLC terminal No. 16 and body ground.
    Fig 3: Measuring Voltage Between Dlc Terminal No. 16 And Body Ground
    G07362037Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 29.

    NO  -Repair an open in the wire between DLC terminal No. 16 and the No. 7 BACK UP (10 A) fuse in the driver's under-dash fuse/relay box.

  29. Measure the voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Measuring Voltage Between Dlc Terminals No. 4 And No. 16
    G07362038Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 30.

    NO  -Repair an open in the wire between DLC terminal No. 4 and body ground (G501) (see DASHBOARD WIRE HARNESS (LEFT BRANCH) ).

  30. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  31. Jump the SCS line with the HDS.
  32. Disconnect PCM connector A (49P).
  33. Disconnect the HDS from the DLC.
  34. Check for continuity between PCM connector terminal A48 and DLC terminal No. 6.
    Fig 5: Checking Continuity Between PCM Connector Terminal A48 And Dlc Terminal No. 6
    G07362039Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 35.

    NO  -Repair an open in the wire between the PCM (A48) and DLC terminal No. 6.

  35. Check for continuity between PCM connector terminal A49 and DLC terminal No. 14.
    Fig 6: Checking Continuity Between PCM Connector Terminal A49 And Dlc Terminal No. 14
    G07362040Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

    NO  -Repair an open in the wire between the PCM (A49) and DLC terminal No. 14.

  36. Try to start the engine.

    Does the engine start and idle? 

    YES  -Go to the F-CAN CIRCUIT TROUBLESHOOTING  .

    NO  -

    • If the starter does not crank, go to step 37.
    • If the starter cranks, turn the ignition switch to LOCK (0), and go to step  39.
  37. Turn the ignition switch to LOCK (0).
  38. Check the No. 23 + B IG MAIN (50 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Repair an open in the wire between the No. 23 + B IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 39.

    NO  -Repair a short in the wire between the No. 23 +B IG MAIN (50 A) fuse and the ignition switch. Also replace the No. 23 +B IG MAIN (50 A) fuse in the under-hood fuse/relay box.

  39. Check the No. 8 Fl ECU (PCM) (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  50.

    NO  -Go to step 40.

  40. Remove the blown No. 8 Fl ECU (PCM) (15 A) fuse from the under-hood fuse/relay box.
  41. Remove PGM-FI main relay 1 (A) from the driver's under-dash fuse/relay box.
    Fig 7: Removing PGM-FI Main Relay 1 From Driver's Under-Dash Fuse/Relay Box
    G07362041Courtesy of AMERICAN HONDA MOTOR CO., INC.
  42. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 4 individually.
    Fig 8: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 1 And No. 4
    G07362042Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 43.

    NO  -Go to step  47.

  43. Disconnect under-hood fuse/relay box connector D (9P).
  44. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 4 individually.
    Fig 9: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 1 And No. 4
    G07362043Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 45.

    NO  -Replace the under-hood fuse/relay box. Also replace the No. 8 Fl ECU (PCM) (15 A) fuse.

  45. Disconnect driver's under-dash fuse/relay box connector D (17P).
  46. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 4 individually.
    Fig 10: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 1 And No. 4
    G07362044Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the driver's under-dash fuse/relay box. Also replace the No. 8 Fl ECU (PCM) (15 A) fuse.

    NO  -Repair a short in the wire between the under-hood fuse/relay box and the driver's under-dash fuse/relay box. Also replace the No. 8 Fl ECU (PCM) (15 A) fuse.

  47. While disconnecting each of the parts or connectors below, one at a time, check for continuity between PGM-FI main relay 4P connector terminal No. 2 and body ground.
    • PGM-FI main relay 2
    • PCM connector B (49P)
    • Each injector 2P connector
    • CMP sensor 3P connector
    • CKP sensor 3P connector
    • MAF sensor/IAT sensor 5P connector
    • ETCS control relay
      Fig 11: Checking Continuity Between PGM-FI Main Relay 4P Connector Terminal No. 2 And Body Ground
      G07362045Courtesy of AMERICAN HONDA MOTOR CO., INC.

      Does continuity go away when one of the above parts or connectors is disconnected? 

      YES  -Replace the part that made the short to body ground go away when disconnected. If the part is the PCM, update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away and the PCM is updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT  ). Also replace the No. 8 Fl ECU (PCM) (15 A) fuse.

      NO  -Go to step 48.

  48. While disconnecting each of the parts or connectors below, one at a time, check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    • PGM-FI main relay 2
    • PCM connector B (49P)
    • Each injector 2P connector
    • CMP sensor 3P connector
    • CKP sensor 3P connector
    • MAF sensor/IAT sensor 5P connector
    • ETCS control relay
  49. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    Fig 12: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
    G07362046Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between PGM-FI main relay 1 and each part. Also replace the No. 8 Fl ECU (PCM) (15A)fuse.

    NO  -Replace the PGM-FI main relay 1. Also replace the No. 8 Fl ECU (PCM) (15 A) fuse.

  50. Check the No. 19 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  60.

    NO  -Go to step 51.

  51. Remove the blown No. 19 FUEL PUMP (20 A) fuse from the driver's under-dash fuse/relay box.
  52. Remove PGM-FI main relay 2 (A) from the driver's under-dash fuse/relay box.
    Fig 13: Removing PGM-FI Main Relay 2 From Driver's Under-Dash Fuse/Relay Box
    G07362047Courtesy of AMERICAN HONDA MOTOR CO., INC.
  53. Test PGM-FI main relay 2 (see POWER RELAY TEST ).

    Is the relay is OK? 

    YES  -Go to step 54.

    NO  -Replace PGM-FI main relay 2. Also replace the No. 19 FUEL PUMP (20 A) fuse.

  54. Check for continuity between PGM-FI main relay 2 4P connector terminal No. 1 and body ground.
    Fig 14: Checking Continuity Between PGM-FI Main Relay 2 4P Connector Terminal No. 1 And Body Ground
    G07362048Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 55.

    NO  -Go to step  58.

  55. Jump the SCS line with the HDS.
  56. Disconnect PCM connector B (49P).
  57. Check for continuity between PCM connector terminal B42 and body ground.
    Fig 15: Checking Continuity Between PCM Connector Terminal B42 And Body Ground
    G07362049Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the No. 19 FUEL PUMP (20 A) fuse and the PCM (B42), between the No. 19 FUEL PUMP (20 A) fuse and PGM-FI main relay 2, or between the No. 19 FUEL PUMP (20 A) fuse and the immobilizer control unit-receiver. Also replace the No. 19 FUEL PUMP (20 A) fuse.

    NO  -Replace the No. 19 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box, and update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT  ).

  58. Disconnect the fuel pump control module 10P connector (see FUEL PUMP CONTROL MODULE REPLACEMENT ).
  59. Check for continuity between fuel pump control module 10P connector terminal No. 3 and body ground.
    Fig 16: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 3 And Body Ground
    G07362050Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the fuel pump control module and PGM-Fl main relay 2. Also replace the No. 19 FUEL PUMP (20 A) fuse.

    NO  -Replace the No. 19 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box, and substitute a known-good fuel pump control module, then recheck. If the symptom/indication goes away with a known-good fuel pump control module, replace the original fuel pump control module.

  60. Jump the SCS line with the HDS.
  61. Disconnect PCM connectors A (49P) and B (49P).
  62. Turn the ignition switch to ON (II).
  63. Measure the voltage between PCM connector terminal B42 and body ground.
    Fig 17: Measuring Voltage Between PCM Connector Terminal B42 And Body Ground
    G07362051Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 64.

    NO  -Repair an open in the wire between the No. 19 FUEL PUMP (20 A) fuse and the PCM (B42).

  64. Measure the voltage between PCM connector terminal A6 and body ground.
    Fig 18: Measuring Voltage Between PCM Connector Terminal A6 And Body Ground
    G07362052Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  70.

    NO  -Go to step 65.

  65. Turn the ignition switch to LOCK (0).
  66. Remove PGM-FI main relay 1 (A) from the driver's under-dash fuse/relay box.
    Fig 19: Removing PGM-FI Main Relay 1 From Driver's Under-Dash Fuse/Relay Box
    G07362053Courtesy of AMERICAN HONDA MOTOR CO., INC.
  67. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 4 and body ground.
    Fig 20: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 4 And Body Ground
    G07362054Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  69.

    NO  -Replace the driver's under-dash fuse/relay box (see DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL/INSTALLATION ).

  68. Connect PGM-FI main relay 1 4P connector terminal No. 3 to body ground with a jumper wire.
    Fig 21: Connecting PGM-FI Main Relay 1 4P Connector Terminal No. 3 To Body Ground With Jumper Wire
    G07362055Courtesy of AMERICAN HONDA MOTOR CO., INC.
  69. Check for continuity between PCM connector terminal A6 and body ground.
    Fig 22: Checking Continuity Between PCM Connector Terminal A6 And Body Ground
    G07362056Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Test PGM-FI main relay 1 (see POWER RELAY TEST ). If the relay is OK, update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT  ).

    NO  -Repair an open in the wire between the PCM (A6) and PGM-FI main relay 1.

  70. Turn the ignition switch to LOCK (0).
  71. Remove PGM-FI main relay 1 (A) from the driver's under-dash fuse/relay box.
    Fig 23: Removing PGM-FI Main Relay 1 From Driver's Under-Dash Fuse/Relay Box
    G07362057Courtesy of AMERICAN HONDA MOTOR CO., INC.
  72. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
    Fig 24: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground
    G07362058Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  74.

    NO  -Replace the driver's under-dash fuse/relay box (see DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL/INSTALLATION ).

  73. Connect PGM-FI main relay 1 4P connector terminal No. 2 to body ground with a jumper wire.
    Fig 25: Connecting PGM-FI Main Relay 1 4P Connector Terminal No. 2 To Body Ground With Jumper Wire
    G07362059Courtesy of AMERICAN HONDA MOTOR CO., INC.
  74. Check for continuity between PCM connector terminal B3 and body ground.
    Fig 26: Checking Continuity Between PCM Connector Terminal B3 And Body Ground
    G07362060Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 75.

    NO  -Repair an open in the wire between the PCM (B3) and the PGM-FI main relay 1.

  75. Test PGM-FI main relay 1 (see POWER RELAY TEST ).

    Is PGM-FI main relay 1 OK? 

    YES  -Go to step 76.

    NO  -Replace PGM-FI main relay 1.

  76. Disconnect PCM connector C (49P).
  77. Check for continuity between body ground and PCM connector terminals A41, B1, B40, B41, C1, and C41 individually.
    Fig 27: Checking Continuity Between Body Ground And PCM Connector Terminals A41
    G07362061Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 28: Checking Continuity Between Body Ground And PCM Connector Terminals A41, B1, B40, B41
    G07362062Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 29: Checking Continuity Between Body Ground And PCM Connector Terminals C1 And C41
    G07362063Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

    NO  -Repair open in the wire(s) between the PCM (A41, B1, B40, B41, C1, C41) and body ground (G101).

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