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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 ).
  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  27.

  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 IMMOBI (immobilizer) system, 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 TPMS, go to step  13.
    • If the HDS does not communicate with the active damper system, go to step  15.
    • If the HDS does not communicate with the ACC system, go to step  17.
    • If the HDS does not communicate with the BODY ELECTRICAL system, go to step  19.
  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  21.

    NO  -Go to the SRS symptom troubleshooting for an SRS indicator that stays on with no stored DTCs (see SRS INDICATOR STAYS ON, BUT NO DTCS ARE STORED, OR CANNOT BE READ ).

  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  21.

    NO  -Go to the VSA symptom troubleshooting for an ABS indicator, brake system indicator, and VSA indicator that do not go off (see ABS INDICATOR, BRAKE SYSTEM INDICATOR, VSA INDICATOR, AND TRAILER STABILITY ASSIST WARNING DO NOT GO OFF ).

  9. Turn the ignition switch to LOCK (0).
  10. 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 SYMPTOM TROUBLESHOOTING INFORMATION ).

    NO  -Go to step  21.

  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  21.

    NO  -Go to the SH-AWD symptom troubleshooting for an SH-AWD indicator that does not go off with no stored DTCs (see DTC 91-1: SH-AWD CONTROL UNIT PROGRAMMING ERROR ).

  13. Turn the ignition switch to LOCK (0).
  14. 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  21.

    NO  -Go to the TPMS symptom troubleshooting for a TPMS indicator that does not go off with no stored DTCs (see TPMS INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED ).

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

    Does the active damper system indicator come on and go off? 

    YES  -Go to step  21.

    NO  -Go to the active damper system symptom troubleshooting for an active damper system indicator that does not go off with no stored DTCs (see SYMPTOM TROUBLESHOOTING ).

  17. Turn the ignition switch to LOCK (0).
  18. 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 symptom troubleshooting for an ACC indicator that does not go off (see ADAPTIVE CRUISE CONTROL (ACC) INDICATOR (AMBER) DOES NOT GO OFF ).

  19. Do the gauge control module self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
  20. Check the gauge display.

    Is B-CAN....ERROR indicated? 

    YES  -Check for B-CAN system DTCs (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS) ).

    NO  -Go to step 21.

  21. Turn the ignition switch to LOCK (0), then do the battery terminal disconnection procedure (see USING THE GR8 BATTERY DIAGNOSTIC STATION ), and wait at least 3 minutes before continuing.
  22. Disconnect the HDS from the DLC.
  23. Check for continuity between DLC terminal No. 7 and body ground.
    Fig 1: Checking Continuity Between DLC Terminal No. 7 And Body Ground
    G08057144Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 24.

    NO  -Go to step  25.

  24. Continue to check for continuity between DLC terminal No. 7 and body ground, while disconnecting these connectors, one at a time:
    • SRS unit connector A (39P)
    • VSA modulator-control unit 46P connector
    • Immobilizer-keyless control unit 7P connector
    • Audio unit connector A (17P) (without navigation)
    • SH-AWD control unit connector A (20P)
    • Active damper control unit connector B (14P) (with active damper)
    • TPMS control unit 20P connector
    • Audio-navigation unit connector A (24P) (with navigation)
    • ACC unit 20P connector (with ACC)
    • MICU connector P (30P)

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

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

    NO  -Repair a 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, the TPMS control unit, the ACC unit, the audio-navigation unit, or the MICU.

  25. 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
    G08057145Courtesy of AMERICAN HONDA MOTOR CO., INC.
  26. Check for continuity between body ground and these connector terminals:
    Connector Terminal
    SRS unit connector A (39P) No. 18 (ORN)
    VSA modulator-control unit 46P connector No. 15 (ORN)
    Immobilizer-keyless control unit 7P connector No. 5 (ORN)
    Audio unit connector A (17P) No. 6 (ORN)
    SH-AWD control unit connector A (20P) No. 5 (ORN)
    Active damper control unit connector B (14P) No. 3 (ORN)
    TPMS control unit 20P connector No. 7 (ORN)
    MICU connector P (30P) No. 6 (ORN)
    ACC unit 20P connector No. 8 (ORN)
    Audio-navigation unit connector A (24P) No. 3 (ORN)

    Is there continuity between the DLC terminal 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 the appropriate connector.

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

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

    YES  -Go to step  38.

    NO  -Go to step 28.

  28. Turn the ignition switch to LOCK (0).
  29. Disconnect the HDS from the DLC.
  30. Measure the voltage between DLC terminal No. 16 and body ground.
    Fig 3: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G08057146Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 31.

    NO  -Repair an 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.

  31. Measure the voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G08057147Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 32.

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

  32. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  33. Jump the SCS line with the HDS.
  34. Disconnect PCM connector A (49P).
  35. Disconnect the HDS from the DLC.
  36. 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
    G08057148Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 37.

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

  37. 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
    G08057149Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Reconnect all connectors, then 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 (A49) and DLC terminal No. 14.

  38. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  -Go to F-CAN CIRCUIT TROUBLESHOOTING 

    NO  -Go to step 39.

  39. Turn the ignition switch to LOCK (0).
  40. Check the No. 3 IG1 MAIN (50 A) fuse in the main under-hood fuse box.

    Is the fuse OK? 

    YES  -Repair an 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 41.

    NO  -Repair a 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.

  41. 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 42.

  42. Remove the blown No. 8 IGP (15 A) fuse from the under-hood fuse/relay box.
  43. Jump the SCS line with the HDS.
  44. Disconnect PCM connector B (49P).
  45. While disconnecting each of the parts or connectors below, one at a time, 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 3P connector
    • MAF sensor/IAT sensor 5P connector
    • Under-hood fuse/relay box connector H (9P)
      Fig 7: Checking Continuity Between PCM Connector Terminal B3 And Body Ground
      G08057150Courtesy of AMERICAN HONDA MOTOR CO., INC.

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

    YES  -Replace the part that made the short to body ground go away when disconnected. Reconnect all connectors, then 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  ). Also replace the No. 8 IGP (15 A) fuse.

    NO  -Go to step 46.

  46. Disconnect these parts or connectors:
    • PGM-FI main relay 2
    • Each injector 2P connector
    • Camshaft position (CMP) sensor 3P connector
    • Crankshaft position (CKP) sensor 3P connector
    • MAF sensor/IAT sensor 5P connector
    • Under-hood fuse/relay box connector H (9P)
  47. Check for continuity between PCM connector terminal B3 and body ground.
    Fig 8: Checking Continuity Between PCM Connector Terminal B3 And Body Ground
    G08057151Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (B3) and each part. Also replace the No. 8 IGP (15 A) fuse.

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

  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  60.

    NO  -Go to step 49.

  49. Remove the blown No. 19 FUEL PUMP (20 A) fuse from the under-dash fuse/relay box.
  50. Remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ), then remove PGM-FI main relay 2 (G) from the under-dash fuse/relay box.
    Fig 9: Identifying PGM-FI Main Relay 2
    G08057152Courtesy of AMERICAN HONDA MOTOR CO., INC.
  51. Test PGM-FI main relay 2 (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -Go to step 52.

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

  52. Check for continuity between PGM-FI main relay 2 4P connector terminal No. 1 and body ground.
    Fig 10: Checking Continuity Between PGM-FI Main Relay 2 4P Connector Terminal No. 1 And Body Ground
    G08057153Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 53.

    NO  -Go to step  56.

  53. Jump the SCS line with the HDS.
  54. Disconnect PCM connector B (49P).
  55. Check for continuity between PCM connector terminal B42 and body ground.
    Fig 11: Checking Continuity Between PCM Connector Terminal B42 And Body Ground
    G08057154Courtesy 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. Also replace the No. 19 FUEL PUMP (20 A) fuse.

    NO  -Replace the No. 19 FUEL PUMP (20 A) fuse in the under-dash fuse/relay box, reconnect all connectors, 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 updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT  ).

  56. Remove the cargo floor lid (see TRIM REMOVAL/INSTALLATION - CARGO AREA ).
  57. On models with active damper, remove the active damper control unit (see ACTIVE DAMPER CONTROL UNIT REPLACEMENT ).
  58. Disconnect the fuel pump control module 10P connector.
  59. Check for continuity between fuel pump control module 10P connector terminal No. 3 and body ground.
    Fig 12: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 3 And Body Ground
    G08057155Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  -Replace the No. 19 FUEL PUMP (20 A) fuse, then substitute a known-good fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ), and recheck. If the symptom/indication goes away with a known-good fuel pump control module, replace the original fuel pump control module (see FUEL PUMP CONTROL MODULE REPLACEMENT ).

  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 13: Measuring Voltage Between PCM Connector Terminal B42 And Body Ground
    G08057156Courtesy 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 14: Measuring Voltage Between PCM Connector Terminal A6 And Body Ground
    G08057157Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  68.

    NO  -Go to step 65.

  65. Turn the ignition switch to LOCK (0).
  66. Disconnect under-hood fuse/relay box connector E (14P).
  67. Check for continuity between PCM connector terminal A6 and under-hood fuse/relay box connector E (14P) terminal No. 5.
    Fig 15: Checking Continuity Between PCM Connector Terminal A6 And Under-Hood Fuse/Relay Box Connector E (14P) Terminal No. 5
    G08057158Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Test PGM-FI main relay 1 (built into the relay control module) (see RELAY CONTROL MODULE TEST ). If PGM-FI main relay 1 is OK, reconnect all connectors, then 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 the under-hood fuse/relay box.

  68. Turn the ignition switch to LOCK (0).
  69. Disconnect under-hood fuse/relay box connector H (9P).
  70. Check for continuity between PCM connector terminal B3 and under-hood fuse/relay box connector H (9P) terminal No. 1.
    Fig 16: Checking Continuity Between PCM Connector Terminal B3 And Under-Hood Fuse/Relay Box Connector H (9P) Terminal No. 1
    G08057159Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 71.

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

  71. Test PGM-FI main relay 1 (built into the relay control module) (see RELAY CONTROL MODULE TEST ).

    Is PGM-FI main relay 1 OK? 

    YES  -Go to step 72.

    NO  -Replace the under-hood fuse/relay box (see DTC B1065: RELAY CONTROL MODULE LOST COMMUNICATION WITH DRIVER'S MPCS UNIT (DRLOCKSW MESSAGE) ).

  72. Disconnect PCM connector C (49P).
  73. Check for continuity between body ground and PCM connector terminals B1, B40, B41, C1, and C41 individually.
    Fig 17: Checking Continuity Between Body Ground And PCM Connector Terminals B1, B40, B41, C1, And C41
    G08057160Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 74.

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

  74. Check for continuity between PCM connector terminal B36 and body ground.
    Fig 18: Checking Continuity Between PCM Connector Terminal B36 And Body Ground
    G08057161Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 75.

    NO  -Go to step  76.

  75. 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 parts is disconnected? 

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

    NO  -Repair a short in the wire between the PCM (B36) and the MAP sensor or the output shaft (countershaft) speed sensor.

  76. Check for continuity between PCM connector terminal C12 and body ground.
    Fig 19: Checking Continuity Between PCM Connector Terminal C12 And Body Ground
    G08057162Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 77.

    NO  -Go to step  78.

  77. Continue to check for continuity between PCM connector terminal C12 and body ground, while disconnecting the input shaft (mainshaft) speed sensor 3P connector.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (C12) and the input shaft (mainshaft) speed sensor.

    NO  -Replace the input shaft (mainshaft) speed sensor (see INPUT SHAFT (MAINSHAFT) SPEED SENSOR REPLACEMENT ).

  78. Check for continuity between PCM connector terminal A24 and body ground.
    Fig 20: Checking Continuity Between PCM Connector Terminal A24 And Body Ground
    G08057163Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 79.

    NO  -Go to step  80.

  79. 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 a short in the wire between the PCM (A24) and the APP sensor.

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

  80. Check for continuity between PCM connector terminal A25 and body ground.
    Fig 21: Checking Continuity Between PCM Connector Terminal A25 And Body Ground
    G08057164Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 81.

    NO  -Go to step  82.

  81. 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 parts is disconnected? 

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

    NO  -Repair a short in the wire between the PCM (A25) and the APP sensor or the FTP sensor.

  82. Check for continuity between PCM connector terminal B18 and body ground.
    Fig 22: Checking Continuity Between PCM Connector Terminal B18 And Body Ground
    G08057165Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 83.

    NO  -Go to step  84.

  83. 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 a short in the wire between the PCM (B18) and the throttle body.

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

  84. Check for continuity between PCM connector terminal C11 and body ground.
    Fig 23: Checking Continuity Between PCM Connector Terminal C11 And Body Ground
    G08057166Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 85.

    NO  -Reconnect all connectors, then 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  ).

  85. Continue to check for continuity between PCM connector terminal C11 and body ground, while disconnecting these parts, one at a time:
    • IMT actuator 5P connector
    • EGR valve 5P connector

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

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

    NO  -Repair a short in the wire between the PCM (C11) and the IMT actuator or the EGR valve.

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