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DLC Circuit Troubleshooting

NOTE: Make sure the HDS operates normally and the DLC cable is in good condition.
  1. Turn the ignition switch OFF.
  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 ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  - Go to step  4.

    NO  - Go to step  23.

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

    Are any Temporary DTCs or DTCs indicated? 

    YES  - Go to the indicated DTCs troubleshooting.

    NO  - Go to step  5.

  5. Turn the ignition switch OFF.
  6. Turn the ignition switch ON (II), and watch the SRS indicator.

    Does the SRS indicator stay on? 

    YES  - Go to the SRS system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  - Go to step  7.

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

    Does the VSA indicator stay on? 

    YES  - Go to the VSA system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  - Go to step  9.

  9. Turn the ignition switch OFF.
  10. Turn the ignition switch ON (II), and watch the SH-AWD indicator.

    Does the SH-AWD indicator stay on? 

    YES  - Go to the SH-AWD system's general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  - Go to step  11.

  11. Turn the ignition switch OFF.
  12. Turn the ignition switch ON (II), and watch the TPMS indicator.

    Does the TPMS indicator stay on? 

    YES  - Go to the TPMS general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

    NO  - Go to step  13.

  13. Turn the ignition switch OFF.
  14. Turn the ignition switch ON (II), and watch the immobilizer indicator.

    Does the immobilizer indicator stay on or flash? 

    YES  - Check symptoms for the immobilizer system.

    NO  - Go to step  15.

  15. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
  16. Check for B-CAN system DTCs without the HDS (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS) ).

    Are any B-CAN DTCs indicated? 

    YES  - Go to the indicated DTCs troubleshooting.

    NO  - Go to step  17.

  17. Turn the ignition switch OFF.
  18. Disconnect the HDS from the DLC.
  19. Check for continuity between DLC terminal No. 7 and body ground.
    Fig 1: Checking Continuity Between DLC Terminal No. 7 And Body Ground
    G05444611Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there 5 Ω or less? 

    YES  - Go to step  20.

    NO  - Go to step  21.

  20. Continue to check for continuity between DLC terminal No. 7 and body ground, while disconnecting these parts, one at a time:
    • SRS unit connector A (28P)
    • VSA modulator-control unit 46P connector
    • SH-AWD control unit connector A (20P)
    • TPMS control unit 20P connector
    • Immobilizer-keyless control unit 7P connector
    • Audio unit 17P connector
    • Under-dash fuse/relay box (Q) (16P) connector

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

      YES  - Replace the part that caused an open when it was disconnected.

      NO  - Repair short in the wire between the DLC (K-line) and the VSA modulator-control unit, the SRS unit, the SH-AWD control unit, the TPMS control unit, the immobilizer-keyless control unit, the audio unit, or the under-dash fuse/relay box.

  21. Connect DLC terminal No. 7 to body ground with a jumper wire.
    Fig 2: Connecting DLC Terminal No. 7 To Body Ground With Jumper Wire
    G05444612Courtesy of AMERICAN HONDA MOTOR CO., INC.
  22. Check for continuity between body ground and these connector terminals:
    TERMINALS REFERENCE CHART

    Connector Terminal
    SRS unit A(28P) No. 24 (LT BLU)
    VSA modulator-control unit 46P No. 15 (LT BLU)
    SH-AWD control unit A (20P) No. 5 (LT BLU)
    TPMS control unit (20P) No. 7 (LT BLU)
    Immobilizer-keyless control unit 7P No. 5 (LT BLU)
    Audio unit 17P No. 6 (LT BLU)
    Under-dash fuse/relay box (Q) (16P) No. 8 (LT BLU)

    Is there continuity between the DLC terminal and each of the terminals in the chart? 

    YES  - Replace the unit which cannot communicate with the HDS.

    NO  - Repair open in the wire between the DLC (K-line) and the appropriate connector.

  23. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
  24. Check for B-CAN system DTCs without the HDS (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS) ).

    Is DTC B1168, B1169, and/or B1178 indicated? 

    YES  - Go to step  37.

    NO  - Go to step  25.

  25. Turn the ignition switch OFF.
  26. Disconnect the HDS from the DLC.
  27. Measure voltage between DLC terminal No. 16 and body ground.
    Fig 3: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G05444613Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  28.

    NO  - Repair open in the wire between DLC terminal No. 16 and the No. 19 Fl MAIN (15A) fuse in the under-hood fuse/relay box.

  28. Measure voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G05444614Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage ? 

    YES  - Go to step  29.

    NO  - Repair open in the wire between DLC terminal No. 4 and body ground (G501) (see DASHBOARD WIRE HARNESS (VIEW OF DRIVER'S SIDE) ).

  29. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  30. Jump the SCS line with the HDS.
  31. Disconnect PCM connector A (44P).
  32. Disconnect the HDS from the DLC.
  33. Connect DLC terminal No. 6 to body ground with a jumper wire.
    Fig 5: Connecting DLC Terminal No. 6 To Body Ground With Jumper Wire
    G05444615Courtesy of AMERICAN HONDA MOTOR CO., INC.
  34. Check for continuity between PCM connector terminal A36 and body ground.
    Fig 6: Checking Continuity Between PCM Connector Terminal A36 And Body Ground
    G05444616Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  35.

    NO  - Repair open in the wire between the PCM (A36) and DLC terminal No. 6.

  35. Connect DLC terminal No. 14 to body ground with a jumper wire.
    Fig 7: Connecting DLC Terminal No. 14 To Body Ground With Jumper Wire
    G05444617Courtesy of AMERICAN HONDA MOTOR CO., INC.
  36. Check for continuity between PCM connector terminal A37 and body ground.
    Fig 8: Checking Continuity Between PCM Connector Terminal A37 And Body Ground
    G05444618Courtesy 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 between the PCM (A37) and DLC terminal No. 14.

  37. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  - Go to F-CAN circuit troubleshooting (Part 1) (see F-CAN CIRCUIT TROUBLESHOOTING (PART 1) ).

    NO  - Go to step  38.

  38. Turn the ignition switch OFF.
  39. Check the No. 2 IG MAIN (50A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  - Repair open in the wire between the No. 2 IG MAIN (50A) fuse and the ignition switch. If the wire is OK, go to step  40.

    NO  - Repair short in the wire between the No. 2 IG MAIN (50A) fuse and the under-hood fuse/relay box. Also replace the No. 2 IG MAIN (50A) fuse.

  40. Inspect the No. 19 Fl MAIN (15A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  47.

    NO  - Go to step  41.

  41. Remove the blown No. 19 Fl MAIN (15A) fuse from the under-hood fuse/relay box.
  42. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
    Fig 9: Identifying PGM-FI Main Relay
    G05444619Courtesy of AMERICAN HONDA MOTOR CO., INC.
  43. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 3 individually.
    Fig 10: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 1 And 3
    G05444620Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ). Also replace the No. 19 Fl MAIN (15A) fuse.

    NO  - Go to step  44.

  44. Disconnect each of the following components, or the connectors from the components, one at a time, and check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    • PGM-FI main relay 2 (FUEL PUMP)
    • PCM connector A (44P)
    • Each injector 2P connector
    • Camshaft position (CMP) sensor B 3P connector
    • Crankshaft position (CKP) sensor 3P connector
    • Electronic throttle control system (ETCS) control relay
    Fig 11: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
    G05444621Courtesy of AMERICAN HONDA MOTOR CO., INC.

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

    YES  - Replace the component that made the short to body ground go away when disconnected. If the item 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 with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ). Also replace the No. 19 Fl MAIN (15A) fuse.

    NO  - Go to step  45.

  45. Disconnect the connectors from these components:
    • PGM-FI main relay 2 (FUEL PUMP)
    • PCM connector A (44P)
    • Injectors
    • Camshaft position (CMP) sensor B
    • Crankshaft position (CKP) sensor
    • Electronic throttle control system (ETCS) control relay
  46. 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
    G05444622Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between PGM-FI main relay 1 and each item. Also replace the No. 19 Fl MAIN (15A) fuse.

    NO  - Replace PGM-FI main relay 1. Also replace the No. 19 Fl MAIN (15A) fuse.

  47. Inspect the No. 2 FUEL PUMP (20A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  54.

    NO  - Go to step  48.

  48. Remove the blown No. 2 FUEL PUMP (20A) fuse from the under-dash fuse/relay box.
  49. Jump the SCS line with the HDS.
  50. Disconnect PCM connector C (44P).
  51. Check for continuity between PCM connector terminal C36 and body ground.
    Fig 13: Checking Continuity Between PCM Connector Terminal C36 And Body Ground
    G05444623Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  52.

    NO  - Replace the No. 2 FUEL PUMP (20A) fuse, 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 with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

  52. Remove the driver's dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ), then remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
    Fig 14: Identifying PGM-FI Main Relay 2 (Fuel Pump)
    G05444624Courtesy of AMERICAN HONDA MOTOR CO., INC.
  53. Check for continuity between PCM connector terminal C36 and body ground.
    Fig 15: Checking Continuity Between PCM Connector Terminal C36 And Body Ground
    G05444625Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the No. 2 FUEL PUMP (20A) fuse and the PCM (C36), between the No. 2 FUEL PUMP (20A) fuse and PGM-FI main relay 2 (FUEL PUMP), or between the No. 2 FUEL PUMP (20A) fuse and the immobilizer-keyless control unit. Also replace the No. 2 FUEL PUMP (20A) fuse.

    NO  - Go to step  54.

  54. Jump the SCS line with the HDS.
  55. Disconnect PCM connectors A (44P) and C (44P).
  56. Turn the ignition switch ON (II).
  57. Measure voltage between PCM connector terminal C36 and body ground.
    Fig 16: Measuring Voltage Between PCM Connector Terminal C36 And Body Ground
    G05444626Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  58.

    NO  - Repair open in the wire between the No. 2 FUEL PUMP (20A) fuse and the PCM (C36).

  58. Measure voltage between PCM connector terminal A6 and body ground.
    Fig 17: Measuring Voltage Between PCM Connector Terminal A6 And Body Ground
    G05444627Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  63.

    NO  - Go to step  59.

  59. Turn the ignition switch OFF.
  60. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
    Fig 18: Identifying PGM-FI Main Relay 1
    G05444628Courtesy of AMERICAN HONDA MOTOR CO., INC.
  61. Measure voltage between PGM-FI main relay 1 4P connector terminal No. 3 and body ground.
    Fig 19: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 3 And Body Ground
    G05444629Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  62.

    NO  - Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).

  62. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 4 and PCM connector terminal A6.
    Fig 20: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 4 And PCM Connector Terminal A6
    G05444630Courtesy 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 with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

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

  63. Turn the ignition switch OFF.
  64. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
    Fig 21: Identifying PGM-FI Main Relay 1
    G05444631Courtesy of AMERICAN HONDA MOTOR CO., INC.
  65. Measure voltage between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
    Fig 22: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground
    G05444632Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  66.

    IMO-Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).

  66. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and PCM connector terminal A8.
    Fig 23: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And PCM Connector Terminal A8
    G05444633Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  67.

    NO  - Repair open in the wire between the PCM (A8) and PGM-FI main relay 1.

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

    Is PGM-FI main relay 1 OK? 

    YES  - Go to step  69.

    NO  - Replace PGM-FI main relay 1.

  68. Jump the SCS line with the HDS.
  69. Disconnect PCM connector B (44P).
  70. Check for continuity between body ground and PCM connector terminals B1, B36, C2, C40, and C44 individually.
    Fig 24: Checking Continuity Between Body Ground And PCM Connector Terminals B1, B36, C2, C40, And C44
    G05444634Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  71.

    NO  - Repair open in the wire between the PCM (B1, B36, C2, C40, C44) and G101 (see ENGINE WIRE HARNESS ).

  71. Check for continuity between PCM connector terminal C13 and body ground.
    Fig 25: Checking Continuity Between PCM Connector Terminal C13 And Body Ground
    G05444635Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  72.

    NO  - Go to step  73.

  72. Continue to check for continuity between PCM connector terminal C13 and body ground, while disconnecting these parts, one at a time:
    • MAP sensor 3P connector
    • Input shaft (mainshaft) speed sensor 3P connector

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

      YES  - Replace the part that caused an open when it was disconnected.

      NO  - Repair short in the wire between the PCM (C13) and the MAP sensor or the input shaft (mainshaft) speed sensor.

  73. Check for continuity between PCM connector terminal B18 and body ground.
    Fig 26: Checking Continuity Between PCM Connector Terminal B18 And Body Ground
    G05444636Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  74.

    NO  - Go to step  75.

  74. Continue to check for continuity between PCM connector terminal B18 and body ground, while disconnecting these parts, one at a time:
    • Turbocharger boost sensor 3P connector
    • Output shaft (countershaft) speed sensor 3P connector

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

      YES  - Replace the part that caused an open when it was disconnected.

      NO  - Repair short in the wire between the PCM (B18) and the turbocharger boost sensor or the output shaft (countershaft) speed sensor.

  75. Check for continuity between PCM connector terminal C12 and body ground.
    Fig 27: Checking Continuity Between PCM Connector Terminal C12 And Body Ground
    G05444637Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  76.

    NO  - Go to step  77.

  76. Continue to check for continuity between PCM connector terminal C12 and body ground, while disconnecting the throttle body 6P connector.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (C12) and the throttle body.

    NO  - Replace the throttle body (see THROTTLE BODY REMOVAL/INSTALLATION ).

  77. Check for continuity between PCM connector terminal A25 and body ground.
    Fig 28: Checking Continuity Between PCM Connector Terminal A25 And Body Ground
    G05444638Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  78.

    NO  - Go to step  79.

  78. Continue to check for continuity between PCM connector terminal A25 and body ground, while disconnecting the APP sensor 6P connector.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (A25) and APP sensor A.

    NO  - Replace the accelerator pedal module (see ACCELERATOR PEDAL MODULE REMOVAL/INSTALLATION ).

  79. Check for continuity between PCM connector terminal A24 and body ground.
    Fig 29: Checking Continuity Between PCM Connector Terminal A24 And Body Ground
    G05444639Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  80.

    NO  - Go to step  81.

  80. Continue to check for continuity between PCM connector terminal A24 and body ground, while disconnecting the APP sensor 6P connector.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (A24) and APP sensor B.

    NO  - Replace the accelerator pedal module (see ACCELERATOR PEDAL MODULE REMOVAL/INSTALLATION ).

  81. Check for continuity between PCM connector terminal A19 and body ground.
    Fig 30: Checking Continuity Between PCM Connector Terminal A19 And Body Ground
    G05444640Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 82.

    NO  - 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 ).

  82. Continue to check for continuity between PCM connector terminal A19 and body ground, while disconnecting these parts, one at a time:
    • A/C pressure sensor 3P connector
    • FTP sensor 3P connector
    • Brake booster pressure sensor 3P connector

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

      YES  - Replace the part that caused an open when it was disconnected.

      NO  - Repair short in the wire between the PCM (A19) and the A/C pressure sensor, the FTP sensor, or the brake booster pressure sensor.

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