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DLC Circuit Troubleshooting

NOTE: Make sure the HDS and the DLC cable of the HDS is normal.
  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  25.

  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 immobilizer indicator.

    Does the immobilizer indicator stay on or flash? 

    YES  - Go to the immobilizer system's troubleshooting (see SYMPTOM TROUBLESHOOTING INFORMATION ).

    NO  - Go to step 11.

  11. Turn the ignition switch OFF.
  12. 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 13.

  13. Turn the ignition switch OFF.
  14. Turn the ignition switch ON (II), and watch the multi-information display.

    Does the TPMS indicator stay on? 

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

    NO  -

    • With active damper system: Go to step 15.
    • Without active damper system: Go to step  17.
  15. Turn the ignition switch OFF.
  16. Turn the ignition switch ON (II), and watch the active damper system indicator.

    Does the active damper system indicator stay on? 

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

    NO  - Go to step 17.

  17. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ) to make sure the gauge is known-good. If the function test is OK, go to step 18.
  18. Check for B-CAN system DTCs without the HDS (see WITHOUT HDS (USE ONLY IF THE HDS IS UNAVAILABLE) ).

    Are any B-CAN DTCs indicated? 

    YES  - Go to the indicated DTCs troubleshooting.

    NO  - Go to step 19.

  19. Turn the ignition switch OFF.
  20. Disconnect the HDS from the DLC.
  21. Check for continuity between DLC terminal No. 7 and body ground.
    Fig 1: Identifying Continuity Between DLC Terminal 7 And Body Ground
    G05485098Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there 5 Ω or less? 

    YES  - Go to step 22.

    NO  - Go to step  23.

  22. 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
    • Immobilizer-keyless control unit 7P connector
    • Audio unit 17P connector
    • SH-AWD control unit 20P connector
    • Active damper control unit 14P connector
    • TPMS control unit 20P connector
    • MICU connector P (30P)

    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 SRS unit, the VSA modulator-control unit, the immobilizer-keyless control unit, the audio unit, the SH-AWD control unit, the active damper control unit, or the TPMS control unit, or the MICU.

  23. Connect DLC terminal No. 7 to body ground with a jumper wire.
    Fig 2: Identifying DLC Terminal 7 To Body Ground With Jumper Wire
    G05485099Courtesy of AMERICAN HONDA MOTOR CO., INC.
  24. Check for continuity between body ground and these connector terminals:
    CONNECTOR TERMINALS CHART

    Connector Terminal
    SRS unit A(28P) No. 24 (LT BLU)
    VSA modulator-control unit 46P No. 15 (LT BLU)
    Immobilizer-keyless control unit 7P No. 5 (LT BLU)
    Audio unit 17P No. 6 (LT BLU)
    SH-AWD control unit 20P No. 5 (LT BLU)
    Active damper control unit 14P No. 3 (LT BLU)
    TPMS control unit 20P No. 7 (LT BLU)
    MICU 30P No. 6 (LT BLU)

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

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

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

  25. Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ) to make sure the gauge is known-good. If the function test is OK, go to step  22.
  26. Check for B-CAN system DTCs without the HDS (see WITHOUT HDS (USE ONLY IF THE HDS IS UNAVAILABLE) ).

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

    YES  - Go to step  39.

    NO  - Go to step 27.

  27. Turn the ignition switch OFF;
  28. Disconnect the HDS from the DLC.
  29. Measure voltage between DLC terminal No. 16 and body ground.
    Fig 3: Identifying Voltage Between DLC Terminal 16 And Body Ground
    G05485100Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 30.

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

  30. Measure voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Identifying Voltage Between DLC Terminals 4 And 16
    G05485101Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 31.

    NO  - Repair open in the wire between DLC terminal No. 4 and G503.

  31. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  32. Jump the SCS line with the HDS.
  33. Disconnect PCM connector A (49P).
  34. Disconnect the HDS from the DLC.
  35. Connect DLC terminal No. 6 to body ground with a jumper wire.
    Fig 5: Identifying DLC Terminal 6 To Body Ground With Jumper Wire
    G05485102Courtesy of AMERICAN HONDA MOTOR CO., INC.
  36. Check for continuity between PCM connector terminal A48 and body ground.
    Fig 6: Identifying Continuity Between PCM Connector Terminal A48 And Body Ground
    G05485103Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 37.

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

  37. Disconnect the jumper wire from DLC terminal No. 6, then connect DLC terminal No. 14 to body ground with a jumper wire.
    Fig 7: Identifying DLC Terminal 14 To Body Ground With Jumper Wire
    G05485104Courtesy of AMERICAN HONDA MOTOR CO., INC.
  38. Check for continuity between PCM connector terminal A49 and body ground.
    Fig 8: Identifying Continuity Between PCM Connector Terminal A49 And Body Ground
    G05485105Courtesy 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 (A49) and DLC terminal No. 14.

  39. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  - Go to F-CAN circuit troubleshooting (see F-CAN Circuit Troubleshooting (Part 1)  ).

    NO  - Go to step 40.

  40. Turn the ignition switch OFF.
  41. Check the No. 3 IG1 MAIN (50 A) fuse in the main under-hood fuse box.

    Is the fuse OK? 

    YES  - Repair open in the wire between the No. 3 IG1 MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 42.

    NO  - Repair short in the wire between the No. 3 IG1 MAIN (50 A) fuse and the main under-hood fuse box. Also replace the No. 3 IG1 MAIN (50 A) fuse.

  42. Inspect the No. 8 IGP (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  48.

    NO  - Go to step 43.

  43. Remove the blown No. 8 IGP (15 A) fuse from the under-hood fuse/relay box.
  44. Jump the SCS line with the HDS.
  45. Disconnect PCM connector B (49P).
  46. Check for continuity between PCM connector terminal B3 and body ground.
    Fig 9: Identifying Continuity Between PCM Connector Terminal B3 And Body Ground
    G05485106Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 47.

    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  ). Also replace the No. 8 IGP (15 A) fuse in the under-hood fuse/relay box.

  47. Disconnect each of the components or connectors below, one at a time, and check for continuity between PCM connector terminal B3 and body ground.
    • PGM-FI main relay 2
    • Each injector 2P connector
    • Camshaft position (CMP) sensor 3P connector
    • Crankshaft position (CKP) sensor 6P connector
    • Under-hood fuse/relay box 9P connector

    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. Also replace the No. 8 IGP (15 A) fuse.

    NO  - Repair short in the wire between the PCM (B3) and the PGM-FI main relay 2, the injector, the CKP sensor, or the under-hood fuse/relay box. Also replace the No, 8 IGP (15 A) fuse in the under-hood fuse/relay box.

  48. Inspect the No. 19 FUEL PUMP (20 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  55.

    NO  - Go to step 49.

  49. Remove the blown No. 19 FUEL PUMP (20 A) fuse in the under-dash fuse/relay box.
  50. Jump the SCS line with the HDS.
  51. Disconnect PCM connector B (49P).
  52. Check for continuity between PCM connector terminal B42 and body ground.
    Fig 10: Identifying Continuity Between PCM Connector Terminal B42 And Body Ground
    G05485107Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 53.

    NO  - Replace the No. 19 FUEL PUMP (20 A) fuse in the 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 with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

  53. Disconnect the dashboard wire harness 39P connector from socket X on the under-dash fuse/relay box (A) (see UNDER-DASH FUSE/RELAY BOX ).
    Fig 11: Identifying Relay Box
    G05485108Courtesy of AMERICAN HONDA MOTOR CO., INC.
  54. Check for continuity between PCM connector terminal B42 and body ground.
    Fig 12: Identifying Continuity Between PCM Connector Terminal B42 And Body Ground
    G05485109Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the under-dash fuse/relay box and the PCM (B42), or between the under-dash fuse/relay box and the immobilizer control unit. Also replace the No. 19 FUEL PUMP (20 A) fuse in the under-dash fuse/relay box.

    NO  - Replace the under-dash fuse/relay box.

  55. Jump the SCS line with the HDS.
  56. Disconnect PCM connectors A (49P) and B (49P).
  57. Turn the ignition switch ON (II).
  58. Measure voltage between PCM connector terminal B42 and body ground.
    Fig 13: Identifying Voltage Between PCM Connector Terminal B42 And Body Ground
    G05485110Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 59.

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

  59. Measure voltage between PCM connector terminal A6 and body ground.
    Fig 14: Identifying Voltage Between PCM Connector Terminal A6 And Body Ground
    G05485111Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  63.

    NO  - Go to step 60.

  60. Turn the ignition switch OFF.
  61. Disconnect the under-hood fuse/relay box 14P connector.
  62. Check for continuity between PCM connector terminal A6 and under-hood fuse/relay box 14P connector terminal No. 5.
    Fig 15: Identifying Continuity Between PCM Connector Terminal A6 And Under-Hood Fuse 14P Connector Terminal 5
    G05485112Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -

    • Replace the under-hood fuse/relay box.
    • 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 the under-hood fuse/relay box.

  63. Turn the ignition switch OFF.
  64. Disconnect the under-hood fuse/relay box 9P connector.
  65. Check for continuity between PCM connector terminal B3 and under-hood fuse/relay box 9P connector terminal No. 1.
    Fig 16: Identifying Continuity Between PCM Connector Terminal B3 And Under-Hood Fuse 9P Connector Terminal 1
    G05485113Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 66.

    NO  - Repair open in the wire between the PCM (B3) and the under-hood fuse/relay box.

  66. Test PGM-FI main relay 1 in the under-hood fuse/ relay box (see POWER RELAY TEST ).

    Is PGM-FI main relay 1 OK? 

    YES  - Go to step 67.

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

  67. Disconnect PCM connector C (49P).
  68. Check for continuity between body ground and PCM connector terminals B1, B40, B41, C1, and C41 individually.
    Fig 17: Identifying Continuity Between Body Ground And PCM Connector Terminals B1 And C41
    G05485114Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 69.

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

  69. Check for continuity between PCM connector terminal B36 and body ground.
    Fig 18: Identifying Continuity Between PCM Connector Terminal B36 And Body Ground
    G05485115Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 70.

    NO  - Go to step  71.

  70. Continue to check for continuity between PCM connector terminal B36 and body ground, while disconnecting these parts, one at a time:
    • MAP 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 (B36) and the MAP sensor, or the output shaft (countershaft) speed sensor.

  71. Check for continuity between PCM connector terminal C12 and body ground.
    Fig 19: Identifying Continuity Between PCM Connector Terminal C12 And Body Ground
    G05485116Courtesy 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 C12 and body ground, while disconnecting these parts, one at a time:
    • EGR valve 6P 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 (C12) and the EGR valve or the input shaft (mainshaft) speed sensor.

  73. Check for continuity between PCM connector terminal A24 and body ground.
    Fig 20: Identifying Continuity Between PCM Connector Terminal A24 And Body Ground
    G05485117Courtesy 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 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 A.

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

  75. Check for continuity between PCM connector terminal A25 and body ground.
    Fig 21: Identifying Continuity Between PCM Connector Terminal A25 And Body Ground
    G05485118Courtesy 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 A25 and body ground, while disconnecting these connectors one at a time.
    • APP sensor 6P connector
    • FTP 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 (A25) and APP sensor B or the FTP sensor.

  77. Check for continuity between PCM connector terminal B18 and body ground.
    Fig 22: Identifying Continuity Between PCM Connector Terminal B18 And Body Ground
    G05485119Courtesy 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 B18 and body ground, while disconnecting the throttle body 6P connector.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (B18) and the throttle body.

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

  79. Check for continuity between PCM connector terminal C11 and body ground.
    Fig 23: Identifying Continuity Between PCM Connector Terminal C11 And Body Ground
    G05485120Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 80.

    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  ).

  80. Continue to check for continuity between PCM connector terminal C11 and body ground, while disconnecting the IMT actuator.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (C11) and the IMT actuator.

    NO  - Replace the IMT actuator (see IMT ACTUATOR REPLACEMENT ).

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