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MIL Circuit Troubleshooting

  1. Turn the ignition switch ON (II).
  2. Do the gauge self-diagnostic procedure (see SELF-DIAGNOSTIC FUNCTION ).

    Does the MIL indicator flash? 

    YES  - Go to step 3.

    NO  - Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module

  3. Turn the ignition switch OFF.
  4. Turn the ignition switch ON (II), and watch the MIL.

    Does the MIL stay off? 

    YES  - Go to step  17.

    NO  - Go to step 5.

  5. Turn the ignition switch OFF.
  6. Turn the ignition switch ON (II), wait 20 seconds, and watch the MIL.

    Does the MIL stay on or flash more than 5 times? 

    YES  - Go to step 7.

    NO  - The MIL circuit is OK

  7. Turn the ignition switch OFF.
  8. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  9. Turn the ignition switch ON (II), and read the HDS.

    Does the HDS communicate with the PCM? 

    YES  - Go to step 10.

    NO  - Go to "DLC CIRCUIT TROUBLESHOOTING "

  10. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    YES  - Go to the indicated DTCs troubleshooting

    NO  - Go to step 11.

  11. Check the MIL in the DATA LIST with the HDS.

    Does it indicate ON? 

    YES  - Go to step 12.

    NO  - Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module

  12. Check the SCS in the DATA LIST with the HDS.

    Is a short indicated? 

    YES  - Go to step 13.

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  13. Turn the ignition switch OFF.
  14. Jump the SCS line with the HDS.
  15. Disconnect PCM connector E (31P), then disconnect the HDS.
  16. Check for continuity between PCM connector terminal E16 and body ground.
    Fig 1: Checking Continuity Between PCM Connector Terminal E16 And Body Ground
    G05494443Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (E16) and the DLC

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  17. Try to start the engine.

    Does the engine start and idle smoothly? 

    YES  - Go to step 18.

    NO  - Go to step  22.

  18. Turn the ignition switch OFF.
  19. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  20. Turn the ignition switch ON (II), and read the HDS.

    Does the HDS communicate with the PCM? 

    YES  - Go to step 21.

    NO  - Go to "DLC CIRCUIT TROUBLESHOOTING "

  21. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC U0073 and/or U0155 indicated? 

    YES  - Go to the indicated DTCs troubleshooting

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  22. Turn the ignition switch OFF.
  23. Inspect the No. 23 +B IG MAIN (50A) 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 (50A) fuse and the ignition switch. If the wire is OK, go to step 24.

    NO  - Repair short in the wire between the No. 23 +B IG MAIN (50A) fuse and the under-hood fuse/relay box. Also replace the No. 23 +B IG MAIN (50A) fuse

  24. Inspect the No. 8 Fl ECU (PCM) (15A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  31.

    NO  - Go to step 25.

  25. Remove the blown No. 8 Fl ECU (PCM) (15A) fuse from the under-hood fuse/relay box.
  26. Remove the left kick panel (see step 3 under TRIM REMOVAL/INSTALLATION - DOOR AREAS ), then remove PGM-FI main relay 1 (Fl MAIN) (A) from the driver's under-dash fuse/relay box.
    Fig 2: Identifying PGM-FI Main Relay 1 (Fl MAIN)
    G05494444Courtesy of AMERICAN HONDA MOTOR CO., INC.
  27. Check for continuity between body ground and PGM-FI main relay 1 (Fl MAIN) 4P connector terminals No. 1 and No. 3 individually.
    Fig 3: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 (FL MAIN) 4P Connector Terminals 1 And 3
    G05494445Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the No. 8 Fl ECU (PCM) (15A) fuse and PGM-FI main relay 1 (Fl MAIN). Also replace the No. 8 Fl ECU (PCM) (15A) fuse

    NO  - Go to step 28.

  28. Disconnect each of the components 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)
    • PCM connector A (31P)
    • Each injector 2P connector
    • Camshaft position (CMP) sensor 3P connector
    • Crankshaft position (CKP) sensor A/B 6P connector
    • A/F sensor relay (LAF) 4P connector
    • Radiator fan control (RFC) relay 4P connector
      Fig 4: Checking Continuity Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal 2 And Body Ground
      G05494446Courtesy of AMERICAN HONDA MOTOR CO., INC.

    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 UPDATING THE PCM ), or substitute a known-good PCM (see HOW TO TROUBLESHOOT CIRCUITS AT THE PCM CONNECTORS ), 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 Fl ECU (PCM) (15A) fuse

    NO  - Go to step 29.

  29. Disconnect the connectors from these components:
    • PGM-FI main relay 2 (FUEL PUMP)
    • PCM connector A (31P)
    • Injectors
    • Camshaft position (CMP) sensor
    • Crankshaft position (CKP) sensor A/B
    • A/F sensor relay (LAF)
    • Radiator fan control (RFC) relay
  30. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 2 and body ground.
    Fig 5: Checking Continuity Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal 2 And Body Ground
    G05494447Courtesy 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 item. Also replace the No. 8 Fl ECU (PCM) (15A) fuse

    NO  - Replace PGM-FI main relay 1 (Fl MAIN). Also replace the No. 8 Fl ECU (PCM) (15A) fuse

  31. Turn the ignition switch ON (II).
  32. Measure voltage between PCM connector terminal D6 and body ground.
    Fig 6: Measuring Voltage Between PCM Connector Terminal D6 And Body Ground
    G05494448Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 33.

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

  33. Measure voltage between PCM connector terminal E5 and body ground.
    Fig 7: Measuring Voltage Between PCM Connector Terminal E5 And Body Ground
    G05494449Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  40.

    NO  - Go to step 34.

  34. Turn the ignition switch OFF.
  35. Remove the left kick panel (see step 3 under TRIM REMOVAL/INSTALLATION - DOOR AREAS ). Then remove PGM-FI main relay 1 (Fl MAIN) (A) from the driver's under-dash fuse/relay box.
    Fig 8: Identifying PGM-FI Main Relay 1 (Fl MAIN)
    G05494450Courtesy of AMERICAN HONDA MOTOR CO., INC.
  36. Measure voltage between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 3 and body ground.
    Fig 9: Measuring Voltage Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal No. 3 And Body Ground
    G05494451Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 37.

    NO  - Repair open in the wire between the No. 8 Fl ECU (PCM) (15A) fuse and PGM-FI main relay 1 (Fl MAIN)

  37. Jump the SCS line with the HDS.
  38. Disconnect PCM connector E (31P).
  39. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 4 and PCM connector terminal E5.
    Fig 10: Checking Continuity Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal 4 And PCM Terminal E5
    G05494452Courtesy 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 PCM if it does not have the latest software (see UPDATING THE PCM ), 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 PGM-FI main relay 1 (Fl MAIN) and the PCM (E5)

  40. Turn the ignition switch ON (II).
  41. Measure voltage between body ground and PCM connector terminal A4.
    Fig 11: Measuring Voltage Between Body Ground And PCM Connector Terminal A4
    G05494453Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  50.

    NO  - Go to step 42.

  42. Turn the ignition switch OFF.
  43. Remove the left kick panel (see step 3 under TRIM REMOVAL/INSTALLATION - DOOR AREAS ). Then remove PGM-FI main relay 1 (Fl MAIN) (A) from the driver's under-dash fuse/relay box.
    Fig 12: Identifying PGM-FI Main Relay 1 (Fl MAIN)
    G05494454Courtesy of AMERICAN HONDA MOTOR CO., INC.
  44. Turn the ignition switch ON (II).
  45. Measure voltage between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 1 and body ground.
    Fig 13: Measuring Voltage Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal 1 And Body Ground
    G05494455Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 46.

    NO  - Repair open in the wire between the No. 8 Fl ECU (PCM) (15A) fuse and PGM-FI main relay 1 (FI MAIN)

  46. Turn the ignition switch OFF.
  47. Jump the SCS line with the HDS.
  48. Disconnect PCM connector A (31P).
  49. Check for continuity between PGM-FI main relay 1 (Fl MAIN) 4P connector terminal No. 2 and PCM connector terminal A4.
    Fig 14: Checking Continuity Between PGM-FI Main Relay 1 (Fl Main) 4P Connector Terminal 2 And PCM Connector Terminal A4
    G05494456Courtesy 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 PCM (A4)

  50. Measure voltage between body ground and PCM connector terminals A1, A2, A3, and B15 individually.
    Fig 15: Measuring Voltage Between Body Ground And PCM Connector Terminals A1, A2, A3, And B15
    G05494457Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there more than 0.2 V? 

    YES  - Repair open in the wire(s) that had more than 0.2 V between G101 and the PCM (A1, A2, A3, and B15)

    NO  - Go to step 51.

  51. Measure voltage between body ground and PCM connector terminal C6.
    Fig 16: Measuring Voltage Between Body Ground And PCM Connector Terminal C6
    G05494458Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Go to step  59.

    NO  - Go to step 52.

  52. Turn the ignition switch OFF.
  53. Disconnect the connector from each of the following sensors, one at a time, and measure voltage between body ground and PCM connector terminal C6 with the ignition switch ON (II).
    • Manifold absolute pressure (MAP) sensor
    • Output shaft (countershaft) speed sensor
      Fig 17: Measuring Voltage Between Body Ground And PCM Connector Terminal C6 With Ignition Switch
      G05494459Courtesy 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 54.

  54. Turn the ignition switch OFF.
  55. Jump the SCS line with the HDS.
  56. Disconnect the connectors from these sensors:
    • Manifold absolute pressure (MAP) sensor
    • Output shaft (countershaft) speed sensor
  57. Disconnect PCM connector C (22P).
  58. Check for continuity between PCM connector terminal C6 and body ground.
    Fig 18: Checking Continuity Between PCM Connector Terminal C6 And Body Ground
    G05494460Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (C6) and the MAP sensor or the output shaft (countershaft) speed sensor

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  59. Measure voltage between body ground and PCM connector terminal C14.
    Fig 19: Measuring Voltage Between Body Ground And PCM Connector Terminal C14
    G05494461Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Go to step  67.

    NO  - Go to step 60.

  60. Turn the ignition switch OFF.
  61. Disconnect the connector from each of the following sensors, one at a time, while measuring voltage between body ground and PCM connector terminal C14 with the ignition switch ON (II).
    • Intake manifold tuning (IMT) actuator
    • Exhaust gas recirculation (EGR) valve
    • Input shaft (mainshaft) speed sensor
      Fig 20: Measuring Voltage Between Body Ground And PCM Connector Terminal C14 With Ignition Switch
      G05494462Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Replace the part that restored 5 V when disconnected

    NO  - Go to step 62.

  62. Turn the ignition switch OFF.
  63. Jump the SCS line with the HDS.
  64. Disconnect the connectors from these parts:
    • Intake manifold tuning (IMT) actuator
    • Exhaust gas recirculation (EGR) valve
    • Input shaft (mainshaft) speed sensor
  65. Disconnect PCM connector C (22P).
  66. Check for continuity between PCM connector terminal C14 and body ground.
    Fig 21: Checking Continuity Between PCM Connector Terminal C14 And Body Ground
    G05494463Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (C14) and the IMT actuator, the EGR valve, or the input shaft (mainshaft) speed sensor

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  67. Measure voltage between body ground and PCM connector terminal D2.
    Fig 22: Measuring Voltage Between Body Ground And PCM Connector Terminal D2
    G05494464Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Go to step  75.

    NO  - Go to step 68.

  68. Turn the ignition switch OFF.
  69. Disconnect the APP sensor 6P connector, and measure voltage between body ground and PCM connector terminal D2 with the ignition switch ON (II).
    Fig 23: Measuring Voltage Between Body Ground And PCM Connector Terminal D2 With Ignition Switch
    G05494465Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Replace the accelerator pedal module (see ACCELERATOR PEDAL MODULE REMOVAL/INSTALLATION )

    NO  - Go to step 70.

  70. Turn the ignition switch OFF.
  71. Jump the SCS line with the HDS.
  72. Disconnect the APP sensor 6P connector.
  73. Disconnect PCM connector D (17P).
  74. Check for continuity between PCM connector terminal D2 and body ground.
    Fig 24: Checking Continuity Between PCM Connector Terminal D2 And Body Ground
    G05494466Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

  75. Measure voltage between PCM connector terminal E12 and body ground.
    Fig 25: Measuring Voltage Between PCM Connector Terminal E12 And Body Ground
    G05494467Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  - Go to step 76.

  76. Turn the ignition switch OFF.
  77. Disconnect the connector, from each of the following sensors, one at a time, and measure voltage between body ground and PCM connector terminal E12 with the ignition switch ON (II).
    Fig 26: Measuring Voltage Between Body Ground And PCM Connector Terminal E12 With Ignition Switch
    G05494468Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  - Repair the sensor that restored 5 V when disconnected

    NO  - Go to step 78.

  78. Turn the ignition switch OFF.
  79. Jump the SCS line with the HDS.
  80. Disconnect the connectors from these sensors:
    • Accelerator pedal position (APP)
    • Fuel tank pressure (FTP) sensor
  81. Disconnect PCM connector E (31P).
  82. Check for continuity between PCM connector terminal E12 and body ground.
    Fig 27: Checking Continuity Between PCM Connector Terminal E12 And Body Ground
    G05494469Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (E12) and the APP sensor or the FTP sensor

    NO  - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), 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  )

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