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DLC Circuit Troubleshooting

NOTE: Make sure the HDS and the HDS DLC cable are not defective.
  1. Turn the ignition switch to LOCK (0).
  2. Connect the HDS to the DLC (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
    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  22.

  4. Check the 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  -Go to step 5.

  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 7.

  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 9.

  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? 

    YES  -Go to the immobilizer system check (see SYSTEM CHECK ).

    NO  -Go to step 11.

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

    Does the EPS indicator stay on? 

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

    NO  -

    • With TPMS: go to step 13.
    • Without TPMS: go to step  15.
  13. Turn the ignition switch to LOCK (0).
  14. Start the engine, and watch the TPMS indicator.

    Does the TPMS indicator stay ON? 

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

    NO  -Go to step 15.

  15. Do the gauge self-diagnostic function without the HDS (see SELF-DIAGNOSTIC FUNCTION ).

    Are all the indicators flashing? 

    YES  -Go to step 16.

    NO  -Troubleshoot the gauge assembly.

  16. Turn the ignition switch to LOCK (0).
  17. Disconnect the HDS from the DLC.
  18. Check for continuity between DLC terminals No. 1 and No. 7 and body ground individually.
    Fig 1: Checking Continuity Between DLC Terminals 1, 7 And Body Ground
    G06231732Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 19.

    NO  -Go to step  20.

  19. Continue to check for continuity between DLC terminals No. 1 and No. 7 and body ground individually, while disconnecting these connectors, one at a time:
    • EPS control unit (14P) connector
    • Immobilizer control unit-receiver (7P) connector
    • SRS unit connector A (28P)
    • VSA modulator-control unit (47P) connector
    • Gauge assembly A (22P) connector
    • TPMS control unit (20P) connector (with TPMS)
    Fig 2: Checking Continuity Between DLC Terminals 1, 7 And Body Ground
    G06231733Courtesy of AMERICAN HONDA MOTOR CO., INC.

    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 (DIAG-H) and the EPS control unit, the immobilizer control unit-receiver, the DLC (K-line), the gauge assembly, the SRS unit, the VSA modulator-control unit, or the TPMS control unit (with TPMS).

  20. Connect DLC terminals No. 1 and No. 7 to body ground with a jumper wire.
    Fig 3: Connecting DLC Terminals 1, 7 To Body Ground With Jumper Wire
    G06231734Courtesy of AMERICAN HONDA MOTOR CO., INC.
  21. Check for continuity between body ground and these connector terminals:
    DLC TERMINAL CHART

    Connector Unit Terminal DLC Terminal
    SRS unit A (28P) No. 24 (GRY) No. 7 (GRY)
    Gauge assembly A (22P) No. 11 (GRY) No. 7 (GRY)
    VSA modulator-control unit (47P) No. 2 (GRY) No. 7 (GRY)
    TPMS control unit (20P) No. 7 (GRY) No. 7 (GRY)
    Immobilizer control unit-receiver (7P) No. 3 (LT BLU) No. 1 (LT BLU)
    EPS control unit (UP) No. 14 (LT BLU) No. 1 (LT BLU)

    Is there continuity between the body ground 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 or DIAG H) and the appropriate connector.

  22. Turn the ignition switch to LOCK (0).
  23. Disconnect the HDS from the DLC.
  24. Measure the voltage between DLC terminal No. 16 and body ground.
    Fig 4: Measuring Voltage Between DLC Terminal No. 16 And Body Ground
    G06231735Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 25.

    NO  -Repair open in the wire between DLC terminal No. 16 and the No. 46 ACGS (15 A) fuse in the under-hood fuse/relay box.

  25. Measure the voltage between DLC terminals No. 4 and No. 16.
    Fig 5: Measuring Voltage Between DLC Terminals No. 4 And No. 16
    G06231736Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 26.

    NO  -Repair open in the wire between the DLC terminal (No. 4) and body ground (G401).

  26. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  27. Jump the SCS line with the HDS.
  28. Disconnect ECM connector E (31P).
  29. Disconnect the HDS from the DLC.
  30. Connect DLC terminal No. 6 to body ground with a jumper wire.
    Fig 6: Connecting DLC Terminal No. 6 To Body Ground With Jumper Wire
    G06231737Courtesy of AMERICAN HONDA MOTOR CO., INC.
  31. Check for continuity between ECM connector terminal E11 and body ground.
    Fig 7: Checking Continuity Between ECM Connector Terminal E11 And Body Ground
    G06231738Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 32.

    NO  -Repair open in the wire between the ECM (E11) and DLC terminal No. 6.

  32. Disconnect the jumper wire.
  33. Connect DLC terminal No. 14 to body ground with a jumper wire.
    Fig 8: Connecting DLC Terminal No. 14 To Body Ground With Jumper Wire
    G06231739Courtesy of AMERICAN HONDA MOTOR CO., INC.
  34. Check for continuity between ECM connector terminal E24 and body ground.
    Fig 9: Checking Continuity Between ECM Connector Terminal E24 And Body Ground
    G06231740Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 35.

    NO  -Repair open in the wire between the ECM (E24) and DLC terminal No. 14.

  35. Try to start the engine.

    Does the engine start and idle smoothly? 

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

    NO  -Go to step 36.

  36. Turn the ignition switch to LOCK (0).
  37. Check the No. 42 IG1 MAIN (40 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Repair open in the wire between the No. 42 IG1 MAIN (40 A) fuse and the ignition switch. If the wire is OK, go to step 38.

    NO  -Repair short in the wire between the No. 42 IG1 MAIN (40 A) fuse and the under-hood fuse/ relay box. Also replace the No. 42 IG1 MAIN (40 A) fuse.

  38. Inspect the No. 46 ACGS (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  45.

    NO  -Go to step 39.

  39. Remove the blown No. 46 ACGS (15 A) fuse from the under-hood fuse/relay box.
  40. Remove PGM-FI main relay 1 (Fl MAIN) (A).
    Fig 10: Identifying PGM-FI Main Relay 1
    G06231741Courtesy of AMERICAN HONDA MOTOR CO., INC.
  41. Check for continuity between body ground and PGM-FI main relay 1 (Fl MAIN) 4P connector terminals No. 1 and No. 4 individually.
    Fig 11: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 4P Connector Terminals 1, 4
    G06231742Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the No. 46 ACGS (15 A) fuse and PGM-FI main relay 1 (Fl MAIN). Also replace the No. 46 ACGS (15 A) fuse.

    NO  -Go to step 42.

  42. Disconnect each of the parts or connectors below, one at a time, while checking for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 2 and body ground.
    • PGM-FI main relay 2 (FUEL PUMP)
    • ECM connector A (31P)
    • Each injector 2P connector
    • Camshaft position (CMP) sensor 3P connector
    • Crankshaft position (CKP) sensor 3P connector
    Fig 12: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And Body Ground
    G06231743Courtesy of AMERICAN HONDA MOTOR CO., INC.

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

    YES  -Replace the part that made continuity to body ground go away when it was disconnected. If the part is the ECM, update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ). Also replace the No. 46 ACGS (15 A) fuse.

    NO  -Go to step 43.

  43. Disconnect the connectors from these parts:
    • PGM-FI main relay 2 (FUEL PUMP)
    • ECM connector A (31P)
    • Injectors
    • CMP sensor
    • CKP sensor
  44. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 2 and body ground.
    Fig 13: Checking Continuity Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal No. 2 And Body Ground
    G06231744Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between PGM-FI main relay 1 (Fl MAIN) and each part. Also replace the No. 46 ACGS (15 A) fuse.

    NO  -Replace PGM-FI main relay 1 (Fl MAIN). Also replace the No. 46 ACGS (15 A) fuse.

  45. Inspect the No. 2 FUEL PUMP SRS (15 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step  57.

    NO  -Go to step 46.

  46. Remove the blown No. 2 FUEL PUMP SRS (15 A) fuse from the under-dash fuse/relay box.
  47. Remove PGM-FI main relay 2 (FUEL PUMP) (A).
    Fig 14: Identifying PGM-FI Main Relay 2
    G06231745Courtesy of AMERICAN HONDA MOTOR CO., INC.
  48. Test PGM-FI main relay 2 (FUEL PUMP) (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -Go to step 49.

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

  49. Check for continuity between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
    Fig 15: Checking Continuity Between PGM-FI Main Relay 2 4P Connector Terminal 1 And Body Ground
    G06231746Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 50.

    NO  -Go to step  53.

  50. Jump the SCS line with the HDS.
  51. Disconnect ECM connector E (31P).
  52. Check for continuity between ECM connector terminal E9 and body ground.
    Fig 16: Checking Continuity Between ECM Connector Terminal E9 And Body Ground
    G06231747Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the No. 2 FUEL PUMP SRS (15 A) fuse, the ECM (E9), and PGM-FI main relay 2 (FUEL PUMP). Also replace the No. 2 FUEL PUMP SRS (15 A) fuse.

    NO  -Go to step 53.

  53. Remove the rear tray (see TRIM REMOVAL/INSTALLATION - REAR TRAY AREA ).
  54. Remove the access panel from the floor.
  55. Disconnect the fuel pump 5P connector.
  56. Check for continuity between fuel pump 5P connector terminal No. 5 and body ground.
    Fig 17: Checking Continuity Between Fuel Pump 5P Connector Terminal No. 5 And Body Ground
    G06231748Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  -Check the fuel pump, and replace it if needed. Also replace the No. 2 FUEL PUMP SRS (15 A) fuse.

  57. Jump the SCS line with the HDS.
  58. Disconnect ECM connector E (31P).
  59. Turn the ignition switch to ON (II).
  60. Measure the voltage between ECM connector terminal E9 and body ground.
    Fig 18: Measuring Voltage Between ECM Connector Terminal E9 And Body Ground
    G06231749Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 61.

    NO  -Repair open in the wire between the No. 2 FUEL PUMP SRS (15 A) fuse and the ECM (E9).

  61. Measure the voltage between ECM connector terminal E7 and body ground.
    Fig 19: Measuring Voltage Between ECM Connector Terminal E7 And Body Ground
    G06231750Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  66.

    NO  -Go to step 62.

  62. Turn the ignition switch to LOCK (0).
  63. Remove PGM-FI main relay 1 (Fl MAIN) (A).
    Fig 20: Identifying PGM-FI Main Relay 1
    G06231751Courtesy of AMERICAN HONDA MOTOR CO., INC.
  64. Measure the voltage between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 4 and body ground.
    Fig 21: Measuring Voltage Between PGM-FI MAIN Relay 1 4P Connector Terminal No. 4 And Body Ground
    G06231752Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 65.

    NO  -Repair open in the wire between the No. 46 ACGS (15 A) fuse and PGM-FI main relay 1 (Fl MAIN).

  65. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 3 and ECM connector terminal E7.
    Fig 22: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 3 And ECM Connector Terminal E7
    G06231753Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Test PGM-FI main relay 1 (Fl MAIN) (see POWER RELAY TEST ). If the relay is OK, update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).

    NO  -Repair open in the wire between PGM-FI main relay 1 (Fl MAIN) and the ECM (E7).

  66. Reconnect ECM connector E (31P).
  67. Turn the ignition switch to ON (II).
  68. Measure the voltage between body ground and ECM connector terminals A2 and A3 individually.
    Fig 23: Measuring Voltage Between Body Ground And ECM Connector Terminals A2 And A3
    G06231754Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  75.

    NO  -Go to step 69.

  69. Turn the ignition switch to LOCK (0).
  70. Remove PGM-FI main relay 1 (Fl MAIN) (A).
    Fig 24: Identifying PGM-FI Main Relay 1
    G06231755Courtesy of AMERICAN HONDA MOTOR CO., INC.
  71. Turn the ignition switch to ON (II).
  72. Measure the voltage between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 1 and body ground.
    Fig 25: Measuring Voltage Between PGM-FI Main Relay 1 4P Connector Terminal No. 1 And Body Ground
    G06231756Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 73.

    NO  -Repair open in the wire between the No. 46 ACGS (15 A) fuse and PGM-FI main relay 1 (Fl MAIN).

  73. Turn the ignition switch to LOCK (0).
  74. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 2 and ECM connector terminals A2 and A3 individually.
    Fig 26: Checking Continuity Between PGM-FI Main Relay 1 4P Connector Terminal No. 2 And ECM Connector Terminals A2
    G06231757Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace PGM-FI main relay 1 (Fl MAIN).

    NO  -Repair open in the wire between PGM-FI main relay 1 (Fl MAIN) and the ECM (A2, A3).

  75. Measure the voltage between body ground and ECM connector terminals A4, A5, A8, A9, and E3 individually.
    Fig 27: Measuring Voltage Between Body Ground And ECM Connector Terminals A4, A5, A8, A9
    G06231758Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there less than 1.0 V? 

    YES  -Go to step 76.

    NO  -Repair open in the wire(s) that had more than 1.0 V between G101 and the ECM (A4, A5, A8, A9, E3).

  76. Measure the voltage between body ground and ECM connector terminal A21.
    Fig 28: Measuring Voltage Between Body Ground And ECM Connector Terminal A21
    G06231759Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Go to step  82.

    NO  -Go to step 77.

  77. Disconnect the MAP sensor 3P connector, and measure the voltage between body ground and ECM connector terminal A21 with the ignition switch turned to ON (II).
    Fig 29: Measuring Voltage Between Body Ground And ECM Connector Terminal A21
    G06231760Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Replace the MAP sensor (see MAP SENSOR REPLACEMENT ).

    NO  -Go to step 78.

  78. Turn the ignition switch to LOCK (0).
  79. Jump the SCS line with the HDS.
  80. Disconnect ECM connector A (31P).
  81. Check for continuity between ECM connector terminal A21 and body ground.
    Fig 30: Checking Continuity Between ECM Connector Terminal A21 And Body Ground
    G06231761Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM (A21) and the MAP sensor.

    NO  -Update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).

  82. Measure the voltage between body ground and ECM connector terminal A20.
    Fig 31: Measuring Voltage Between Body Ground And ECM Connector Terminal A20
    G06231762Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Go to step  90.

    NO  -Go to step 83.

  83. Turn the ignition switch to LOCK (0).
  84. Disconnect the connector from the following sensors, one at a time, while measuring the voltage between body ground and ECM connector terminal A20 with the ignition switch in ON (II).
    • Accelerator pedal position (APP) sensor
    • Output shaft (countershaft) speed sensor
    Fig 32: Measuring Voltage Between Body Ground And ECM Connector Terminal A20
    G06231763Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Replace the sensor that restored 5 V when disconnected.

    NO  -Go to step 85.

  85. Turn the ignition switch to LOCK (0).
  86. Jump the SCS line with the HDS.
  87. Disconnect the connectors from these sensors:
    • Accelerator pedal position (APP) sensor
    • Output shaft (countershaft) speed sensor
  88. Disconnect ECM connector A (31P).
  89. Check for continuity between ECM connector terminal A20 and body ground.
    Fig 33: Checking Continuity Between ECM Connector Terminal A20 And Body Ground
    G06231764Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM (A20) and the APP sensor or output shaft (countershaft) speed sensor.

    NO  -Update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).

  90. Measure the voltage between body ground and ECM connector terminal E5.
    Fig 34: Measuring Voltage Between Body Ground And ECM Connector Terminal E5
    G06231765Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).

    NO  -Go to step 91.

  91. Turn the ignition switch to LOCK (0).
  92. Disconnect the connectors from the following sensors, one at time, while measuring the voltage between body ground and ECM connector terminal E5 with the ignition switch in ON (II).
    • Fuel tank pressure (FTP) sensor
    • Accelerator pedal position (APP) sensor
    Fig 35: Measuring Voltage Between Body Ground And ECM Connector Terminal E5
    G06231766Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Replace the sensor that restored 5 V when it was disconnected.

    NO  -Go to step 93.

  93. Turn the ignition switch to LOCK (0).
  94. Jump the SCS line with the HDS.
  95. Disconnect the connectors from these sensors:
    • Fuel tank pressure (FTP) sensor
    • Accelerator pedal position (APP) sensor
  96. Disconnect ECM connector E (31P).
  97. Check for continuity between ECM connector terminal E5 and body ground.
    Fig 36: Checking Continuity Between ECM Connector Terminal E5 And Body Ground
    G06231767Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM (E5) and the FTP sensor or the APP sensor.

    NO  -Update the ECM if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).

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