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DLC Circuit Troubleshooting

NOTE: Make sure the HDS and the DLC cable of the HDS are not defective.
  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 Temporary DTCs or DTCs in the PGM-FI system with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    YES  -Go to the indicated DTC's troubleshooting.

    NO  -

    • If the HDS does not communicate with the SRS system, 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 stay on? 

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

    NO  -Go to step  19.

  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 stay on? 

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

    NO  -Go to step  19.

  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 stay on? 

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

    NO  -Go to step  19.

  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 stay on? 

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

    NO  -Go to step  19.

  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 stay on? 

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

    NO  -Go to step  19.

  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).
  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
    G06163902Courtesy 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 47P connector
    • TPMS control unit connector B (20P)
    • Immobilizer-keyless control unit 7P connector
    • SH-AWD control unit connector A (26P)
    • ACC unit 20P connector
    • Driver's under-dash fuse/relay box (P) (30P) connector
    • 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 an open when it was disconnected.

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

  23. Connect DLC terminals No. 1 and No. 7 to body ground with a jumper wire.
    Fig 2: Connecting DLC Terminals No. 1 And No. 7 To Body Ground With Jumper Wire
    G06163903Courtesy of AMERICAN HONDA MOTOR CO., INC.
  24. Check for continuity between body ground and these connector terminals:
    TERMINAL CONNECTOR REFERENCE CHART

    Connector Terminal
    SRS unit A (28P) No. 24 (RED)
    VSA modulator-control unit 47 P No. 11 (RED)
    TPMS control unit B (20P) No. 9 (RED)
    Immobilizer-keyless control unit 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 (P) (30P) No. 6 (RED)
    Keyless access control unit A (31P) No. 6 (GRY)

    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 open in the wire between the DLC (K-line and DIAG-H line) and the appropriate connector.

  25. 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  39.

    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
    G06163904Courtesy 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. 16 and the No. 7 BACK UP (10 A) fuse in the 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
    G06163905Courtesy 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. 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 E (31P).
  33. Disconnect the HDS from the DLC.
  34. 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
    G06163906Courtesy of AMERICAN HONDA MOTOR CO., INC.
  35. Check for continuity between PCM connector terminal E15 and body ground.
    Fig 6: Checking Continuity Between PCM Connector Terminal E15 And Body Ground
    G06163907Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 36.

    NO  -Repair open in the wire between the PCM (E15) and DLC terminal No. 6.

  36. 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
    G06163908Courtesy of AMERICAN HONDA MOTOR CO., INC.
  37. Check for continuity between PCM connector terminal E26 and body ground.
    Fig 8: Checking Continuity Between PCM Connector Terminal E26 And Body Ground
    G06163909Courtesy 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 (E26) 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 (see F-CAN CIRCUIT TROUBLESHOOTING ).

    NO  -Go to step 39.

  39. Turn the ignition switch to LOCK (0).
  40. Check the No. 23 +B IG MAIN (50 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Repair 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 41.

    NO  -Repair 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.

  41. Inspect the No. 23 IGP (7.5 A) fuse in the driver's under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  47.

    NO  -Go to step 42.

  42. Remove the blown No. 23 IGP (7.5 A) fuse from the driver's under-dash fuse/relay box.
  43. Jump the SCS line with the HDS.
  44. Disconnect PCM connector A (31P).
  45. Check for continuity between PCM connector terminal A4 and body ground.
    Fig 9: Checking Continuity Between PCM Connector Terminal A4 And Body Ground
    G06163910Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 46.

    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. 23 IGP (7.5 A) fuse in the driver's under-hood fuse/relay box.

  46. Disconnect each of the components or connectors below, one at a time, and check for continuity between PCM connector terminal A4 and body ground.
    • Each injector 2P connector
    • Camshaft position (CMP) sensor 3P connector
    • Crankshaft position (CKP) sensor A/B 6P connector
    • Driver's under-dash fuse/relay box 39P 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. 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. 23 IGP (7.5 A) fuse.

    NO  -Repair short in the wire between the PCM (A4) and the injector, the CMP sensor, the CKP sensor, or the driver's under-dash fuse/relay box. Also replace the No. 23 IGP (7.5 A) fuse in the driver's under-hood fuse/relay box.

  47. Inspect 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  57.

    NO  -Go to step 48.

  48. Remove the blown No. 19 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box.
  49. Remove PGM-FI main relay 2 (A) from the driver's under-dash fuse/relay box.
    Fig 10: Identifying PGM-FI Main Relay Of Driver's Under-Dash Fuse/Relay Box
    G06163911Courtesy of AMERICAN HONDA MOTOR CO., INC.
  50. Test PGM-FI main relay 2 (FUEL PUMP).

    Is relay is OK? 

    YES  -Go to step 51.

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

  51. Check for continuity between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
    Fig 11: Checking Continuity Between PGM-FI Main Relay (Fuel Pump) 4P Connector Terminal No. 1 And Body Ground
    G06163912Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 52.

    NO  -Go to step  55.

  52. Jump the SCS line with the HDS.
  53. Disconnect PCM connector D (17P).
  54. Check for continuity between PCM connector terminal D6 and body ground.
    Fig 12: Checking Continuity Between PCM Connector Terminal D6 And Body Ground
    G06163913Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the No. 19 FUEL PUMP (20 A) fuse and the PCM (D6), between the No. 19 FUEL PUMP (20 A) fuse and PGM-FI main relay 2. Also replace the No. 19 FUEL PUMP (20 A) fuse in the driver's under-dash fuse/relay box.

    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 with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

  55. Disconnect the fuel pump control module 10P connector (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT ).
  56. Check for continuity between the fuel pump control module 10P connector terminal No. 3 and body ground.
    Fig 13: Checking Continuity Between Fuel Pump Control Module 10P Connector Terminal No. 3 And Body Ground
    G06163914Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  -Check the fuel pump control module, and replace it if necessary (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT ). Also replace the No. 19 FUEL PUMP (20 A) fuse.

  57. Jump the SCS line with the HDS.
  58. Disconnect PCM connectors D (17P) and E (31P).
  59. Turn the ignition switch to ON (II).
  60. Measure the voltage between PCM connector terminal D6 and body ground.
    Fig 14: Measuring Voltage Between PCM Connector Terminal D6 And Body Ground
    G06163915Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 61.

    NO  -Repair open in the wire between the No. 19 FUEL PUMP (20 A) fuse and the PCM (D6).

  61. Measure the voltage between PCM connector terminal E5 and body ground.
    Fig 15: Measuring Voltage Between PCM Connector Terminal E5 And Body Ground
    G06163916Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  68.

    NO  -Go to step 62.

  62. Turn the ignition switch to LOCK (0).
  63. Disconnect the driver's under-dash fuse/relay box 39P connector.
  64. Check for continuity between PCM connector terminal E5 and driver's under-dash fuse/relay box 39P connector terminal No. 1.
    Fig 16: Checking Continuity Between PCM E5 And Driver's Under-Dash Fuse/Relay Box 39P Connector Terminal No. 1
    G06163917Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 65.

    NO  -Repair open in the wire between the PCM (E5) and the driver's under-dash fuse/relay box.

  65. Reconnect the driver's under-dash fuse/relay box connector X (39P).
  66. Remove PGM-FI main relay 1 (F1 MAIN) (A) from the driver's under-dash fuse/relay box connector X (39P).
    Fig 17: Identifying PGM-FI Main Relay 1 (F1 MAIN) Location
    G00491212Courtesy of AMERICAN HONDA MOTOR CO., INC.
  67. Check for continuity between PGM-FI main relay 1 (F1 MAIN) 4P connector terminal No. 3 and driver's under-dash fuse/relay box 39P connector terminal No. 1.
    Fig 18: Checking Continuity Between PGM-FI Main Relay 1 (F1 MAIN) 4P Connector Terminal No. 3 And Driver's Under-Dash Fuse/Relay Box 39P Connector Terminal No. 1
    G00491721Courtesy 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  -Replace the driver's under-dash fuse/relay box.

  68. Turn the ignition switch to LOCK (0).
  69. Disconnect the driver's under-dash fuse/relay box 39P connector.
  70. Check for continuity between PCM connector terminal A4 and driver's under-dash fuse/relay box 39P connector terminal No. 31.
    Fig 19: Checking Continuity Between PCM A4 And Driver's Under-Dash Fuse/Relay Box 39P Connector Terminal No. 31
    G06163918Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 68.

    NO  -Repair open in the wire between the PCM (A4) and the driver's under-dash fuse/relay box.

  71. Test PGM-FI main relay 1 in the driver's under-dash fuse/relay box (see POWER RELAY TEST ).

    Is PGM-FI main relay 1 OK? 

    YES  -Go to step 69.

    NO  -Replace PGM-FI main relay 1.

  72. Disconnect PCM connector B (24P).
  73. Check for continuity between body ground and PCM connector terminals A1, A2, A3, and B15 individually.
    Fig 20: Checking Continuity Between Body Ground And PCM Connector Terminals A1, A2, A3, And B15
    G06163919Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 71.

    NO  -Repair open in the wire between the PCM (A1, A2, A3, B15) and G101.

  74. Disconnect PCM connector C (22P).
  75. Check for continuity between PCM connector terminal C6 and body ground.
    Fig 21: Checking Continuity Between PCM Connector Terminal C6 And Body Ground
    G06163920Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 73.

    NO  -Go to step  77.

  76. Continue to check for continuity between PCM connector terminal C6 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 (C6) and the MAP sensor, the output shaft (countershaft) speed sensor.

  77. Check for continuity between PCM connector terminal C14 and body ground.
    Fig 22: Checking Continuity Between PCM Connector Terminal C14 And Body Ground
    G06163921Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 75.

    NO  -Go to step  79.

  78. Continue to check for continuity between PCM connector terminal C14 and body ground, while disconnecting these parts, one at a time:
    • EGR valve 5P connector
    • Input shaft (mainshaft) speed sensor 3P connector
    • IMT actuator 5P 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 (C14) and the EGR valve, the input shaft (mainshaft) speed sensor, or the IMT actuator.

  79. Check for continuity between PCM connector terminal D2 and body ground.
    Fig 23: Checking Continuity Between PCM Connector Terminal D2 And Body Ground
    G06163922Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 77.

    NO  -Go to step  79.

  80. Continue to check for continuity between PCM connector terminal D2 and body ground, while disconnecting the APP sensor 6P connector.

    Is there continuity? 

    YES  -Repair short in the wire between the PCM (D2) and APP sensor A.

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

  81. Check for continuity between PCM connector terminal E12 and body ground.
    Fig 24: Checking Continuity Between PCM Connector Terminal E12 And Body Ground
    G06163923Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 79.

    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 E12 and body ground, while disconnecting these connectors one at a time.
    • APP sensor 6P connector
    • FTP sensor 6P 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 (E12) and the APP sensor B or the FTP sensor.

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