2012 Honda Insight BaseFACTORY OEM SERVICE PROCEDURE

DLC Circuit Troubleshooting

NOTE: If you suspect the HDS or 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 problem.
  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  23.

  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 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 EPS system, go to step  9.
    • If the HDS does not communicate with the TPMS system, go to step  11.
    • If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step  13.
    • If the HDS does not communicate with the BODY ELECTRICAL system, go to step  15.
  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  17.

    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  17.

    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 (RED), VSA INDICATOR, AND BRAKE SYSTEM INDICATOR (AMBER) DO NOT GO OFF ).

  9. Turn the ignition switch to LOCK (0).
  10. Start the engine, and watch the EPS indicator.

    Does the EPS indicator come on and go off? 

    YES  -Go to step  17.

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

  11. Turn the ignition switch to LOCK (0).
  12. 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  17.

    NO  -Go to the TPMS symptom troubleshooting for TPMS indicator does not go off, and no DTC stored (see LOW TIRE PRESSURE/TPMS INDICATOR DOES NOT GO OFF, AND NO DTCS ARE STORED ).

  13. Turn the ignition switch to LOCK (0).
  14. 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  17.

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

    Is Error 2 indicated? 

    YES  -Check for B-CAN system DTCs.

    NO  -Go to step 17.

  17. Turn the ignition switch to LOCK (0), then do the 12 volt battery terminal disconnection procedure (see USING THE GR8 BATTERY DIAGNOSTIC STATION ), and wait at least 3 minutes before continuing.
  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
    G08092344Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    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 (39P)
    • VSA modulator-control unit 47P connector
    • EPS control unit connector C (16P)
    • TPMS control unit 20P connector
    • Immobilizer-keyless control unit 7P connector
    • Audio-navigation unit connector A (24P)
    • Audio unit connector A (24P)
    • Under-dash fuse/relay box connector Q (16P)

    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 the DLC (K-line) and the VSA modulator-control unit, the SRS unit, the EPS control unit, the immobilizer-keyless control unit, the audio-navigation 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 Using Jumper Wire
    G08092345Courtesy of AMERICAN HONDA MOTOR CO., INC.
  22. Check for continuity between body ground and these connector terminals:
    Connector Terminal
    SRS unit A(39P) No. 18 (BLU)
    VSA control unit 47P No. 10 (RED)
    EPS control unit C (16P) No. 16 (RED)
    TPMS control unit 20P No. 7 (BLU)
    Immobilizer-keyless control unit 7P No. 5 (BLU)
    Audio-navigation unit A (24P) No. 3 (BLU)
    Audio unit A (24P) No. 3 (BLU)
    Under-dash fuse/relay box Q(16P) No. 2 (BLU)

    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 the appropriate connector.

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

    Is DTC U0029 and/or U0100 indicated? 

    YES  -Go to step  34.

    NO  -Go to step 24.

  24. Turn the ignition switch to LOCK (0).
  25. Disconnect the HDS from the DLC.
  26. Measure the voltage between DLC terminal No. 16 and body ground.
    Fig 3: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G08092346Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 27.

    NO  -Repair an open in the wire between DLC terminal No. 16 and the No. 1 BACK UP (15A) fuse in the under-dash fuse/relay box.

  27. Measure the voltage between DLC terminals No. 4 and No. 16.
    Fig 4: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G08092347Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 28.

    NO  -Repair an open in the wire between DLC terminal No. 4 and body ground (G502) (see CONNECTOR TO FUSE/RELAY BOX INDEX ).

  28. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  29. Jump the SCS line with the HDS.
  30. Disconnect PCM connector A (49P).
  31. Disconnect the HDS from the DLC.
  32. Check for continuity between PCM connector terminal A3 and DLC terminal No. 6.
    Fig 5: Checking Continuity Between PCM Connector Terminal A3 And DLC Terminal No. 6
    G08092348Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 33.

    NO  -Repair an open in the wire between the PCM (A3) and DLC terminal No. 6.

  33. Check for continuity between PCM connector terminal A4 and DLC terminal No. 14.
    Fig 6: Checking Continuity Between PCM Connector Terminal A4 And DLC Terminal No. 14
    G08092349Courtesy 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 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 (A4) and DLC terminal No. 14.

  34. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  -Go to F-CAN CIRCUIT TROUBLESHOOTING  (see ).

    NO  -Go to step 35.

  35. Turn the ignition switch to LOCK (0).
  36. Check the No. 60 IG SW (50 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Repair an open in the wire between the No. 60 IG SW (50 A) fuse and the ignition switch. If the wire is OK go to step 37.

    NO  -Repair a short in the wire between the No. 60 IG SW (50 A) fuse and the under-dash fuse/relay box. Also replace the No. 60 IG SW (50 A) fuse.

  37. Inspect the No. 39 IGP (15 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  44.

    NO  -Go to step 38.

  38. Remove the blown No. 39 IGP (15 A) fuse from the under-dash fuse/relay box.
  39. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
    Fig 7: Identifying Fuse Access Panel And PGM-FI Main Relay 1
    G08092350Courtesy of AMERICAN HONDA MOTOR CO., INC.
  40. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 2 and No. 3 individually.
    Fig 8: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals No. 2 And No. 3
    G08092351Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ).

    NO  -Go to step 41.

  41. 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. 1 and body ground.
    • PGM-FI main relay 2
    • PCM connector A (49P)
    • Each injector 2P connector
    • CMP sensor 3P connector
    • CKP sensor 3P connector
    • Electronic throttle control system (ETCS) control relay
      Fig 9: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground.
      G08092352Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Does continuity go away when one of the above parts or components 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 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. 39 IGP (15 A) fuse.

    NO  -Go to step 42.

  42. Disconnect the connectors from these parts:
    • PGM-FI main relay 2
    • PCM connector A (49P)
    • Each injector 2P connector
    • CMP sensor 3P connector
    • CKP sensor 3P connector
    • Electronic throttle control (ETCS) control relay
  43. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
    Fig 10: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground
    G08092353Courtesy 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. 39 IGP (15A)fuse.

    NO  -Replace PGM-FI main relay 1. Also replace the No. 39 IGP (15A)fuse.

  44. Inspect the No. 20 FUEL PUMP (15 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  54.

    NO  -Go to step 45.

  45. Remove the blown No. 20 FUEL PUMP (15 A) fuse from the under-dash fuse/relay box.
  46. Remove PGM-FI main relay 2 (A) from the auxiliary under-hood fuse/relay box.
    Fig 11: Identifying PGM-FI Main Relay 2
    G08092354Courtesy of AMERICAN HONDA MOTOR CO., INC.
  47. Test PGM-FI main relay 2 (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -Go to step 48.

    NO  -Replace PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP (15 A) fuse.

  48. Check for continuity between PGM-FI main relay 2 4P connector terminal No. 1 and body ground.
    Fig 12: Checking Continuity Between PGM-FI Main Relay 2 4P Connector Terminal No. 1 And Body Ground
    G08092355Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 49.

    NO  -Go to step  52.

  49. Jump the SCS line with the HDS.
  50. Disconnect PCM connector C (49P).
  51. Check for continuity between PCM connector terminal C10 and body ground.
    Fig 13: Checking Continuity Between PCM Connector Terminal C10 And Body Ground
    G08092356Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the No. 20 FUEL PUMP (15 A) fuse and the PCM (C10) or PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP (15A)fuse.

    NO  -Replace the No. 20 FUEL PUMP (15 A) 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 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  ).

  52. Disconnect the fuel pump 4P connector (see FUEL TANK UNIT REMOVAL AND INSTALLATION ).
  53. Check for continuity between fuel pump 4P connector terminal No. 2 and body ground.
    Fig 14: Checking Continuity Between Fuel Pump 4P Connector Terminal No. 2 And Body Ground
    G08092357Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the fuel pump and PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP(15A)fuse.

    NO  -Check the fuel pump, and replace it if needed (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT ). Also replace the No. 20 FUEL PUMP (15 A) fuse.

  54. Jump the SCS line with the HDS.
  55. Disconnect PCM connectors A (49P) and C (49P).
  56. Turn the ignition switch to ON (II).
  57. Measure the voltage between PCM connector terminal C10 and body ground.
    Fig 15: Measuring Voltage Between PCM Connector Terminal C10 And Body Ground
    G08092358Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 58.

    NO  -Repair an open in the wire between the No. 20 FUEL PUMP (15 A) fuse and the PCM (C10).

  58. Measure the voltage between PCM connector terminal A7 and body ground.
    Fig 16: Measuring Voltage Between PCM Connector Terminal A7 And Body Ground
    G08092359Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  64.

    NO  -Go to step 59.

  59. Turn the ignition switch to LOCK (0).
  60. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
    Fig 17: Identifying Fuse Access Panel And PGM-FI Main Relay 1
    G08092360Courtesy of AMERICAN HONDA MOTOR CO., INC.
  61. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 3 and body ground.
    Fig 18: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 3 And Body Ground
    G08092361Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 62.

    NO  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ).

  62. Connect PGM-FI main relay 1 4P connector terminal No. 4 to body ground with a jumper wire.
    Fig 19: Connecting PGM-FI Main Relay 1 4P Connector Terminal No. 4 To Body Ground Using Jumper Wire
    G08092362Courtesy of AMERICAN HONDA MOTOR CO., INC.
  63. Check for continuity between PCM connector terminal A7 and body ground.
    Fig 20: Checking Continuity Between PCM Connector Terminal A7 And Body Ground
    G08092363Courtesy 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 (A7) and PGM-FI main relay 1.

  64. Turn the ignition switch to LOCK (0).
  65. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
    Fig 21: Identifying Fuse Access Panel And PGM-FI Main Relay 1
    G08092364Courtesy of AMERICAN HONDA MOTOR CO., INC.
  66. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
    Fig 22: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
    G08092365Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 67.

    NO  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ).

  67. Connect PGM-FI main relay 1 4P connector terminal No. 1 to body ground with a jumper wire.
    Fig 23: Connecting PGM-FI Main Relay 1 4P Connector Terminal No. 1 To Body Ground Using Jumper Wire
    G08092366Courtesy of AMERICAN HONDA MOTOR CO., INC.
  68. Check for continuity between body ground and PCM connector terminals A9 individually.
    Fig 24: Checking Continuity Between Body Ground And PCM Connector Terminals A9
    G08092367Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Remove the jumper wire, then go to step 69.

    NO  -Repair an open in the wire between the PCM (A9) and PGM-FI main relay 1.

  69. Disconnect PCM connector B (49P).
  70. Check for continuity between body ground and PCM connector terminals B1, B10, C2, C44, and C49 individually.
    Fig 25: Checking Continuity Between Body Ground And PCM Connector B Terminals B1, B10, C2, C44, And C49
    G08092368Courtesy of AMERICAN HONDA MOTOR CO., INC.
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