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MIL Circuit Troubleshooting

  1. Turn the ignition switch ON (II).
  2. Do the gauge self-diagnostic function (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 (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 " (see ). If no problem is found in the DLC troubleshooting, go to step  21.

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

    Are any Temporary DTCs or DTCs indicated? 

    YES  - Go to the indicated DTC'S 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, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). 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 A (44P).
  16. Check for continuity between PCM Connector terminal A31 and body ground.
    Fig 1: Checking Continuity Between PCM Connector Terminal A31 And Body Ground
    G04546005Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the PCM (A31) and the DLC.

    NO  - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). 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 (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  22.

    NO  - Go to "DLC CIRCUIT TROUBLESHOOTING " (see ). If no problem is found in the DLC troubleshooting, go to step 21.

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

    Is DTC U0073 and/or U0155 indicated? 

    YES  - Go to the indicated DTC TROUBLESHOOTING .

    NO  - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

  22. Turn the ignition swtich OFF.
  23. Inspect the No. 42 +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. 42 +B IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 24.

    NO  - Repair short in the wire between No. 42 +B IG MAIN (50 A) fuse and the driver's under-dash fuse/relay box. Also replace the No. 42 +B IG MAIN (50 A) fuse.

  24. Inspect the No. 46 ACGS (15 A) 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. 46 ACGS (15 A) fuse from the under-hood fuse/relay box.
  26. Remove PGM-FI main relay 1 (FI MAIN) (A).
    Fig 2: Removing PGM-FI Main Relay 1 (FI Main)
    G04546006Courtesy of AMERICAN HONDA MOTOR CO., INC.
  27. Check for continuity between body ground and PGM-FI main relay 1 (FI MAIN) 4P Connector terminals No. 1 and No. 3 individually.
    Fig 3: Checking Continuity Between Body Ground And PGM-FI Main Relay 1 (FI Main) 4P Connector Terminals No. 1 And No. 3
    G04546007Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  - Go to step 28.

  28. Disconnect each of the components or Connectors below, one at a time, and check for continuity between PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 2 and body ground.
    • PGM-FI main relay 2 (FUEL PUMP)
    • PCM Connector B (44P)
    • Each injector 2P Connector
    • Camshaft position (CMP) sensor 3P Connector
    • Crankshaft position (CKP) sensor A/B 6P Connector
    • Electronic throttle control system (ETCS) control relay
      Fig 4: Checking Continuity Between PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 2 And Body Ground
      G04546008Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 29.

    NO  - 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, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ). Also replace the No. 46 ACGS (15 A) fuse.

  29. Disconnect the Connectors of all these components.
    • PGM-FI main relay 2 (FUEL PUMP)
    • PCM Connector B (44P)
    • Injectors
    • Camshaft position (CMP) sensor
    • Crankshaft position (CKP) sensor A/B
    • Electronic throttle control system (ETCS) control relay
  30. Check for continuity between PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 2 and body ground.
    Fig 5: Checking Continuity Between PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 2 And Body Ground
    G04546009Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

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

  31. Inspect the No. 1 FUEL PUMP (15 A) fuse in the driver's under-dash fuse/relay box.

    Is the fuse OK? 

    YES  - Go to step  44.

    NO  - Go to step 32.

  32. Remove the blown No. 1 IG FUEL PUMP (15 A) fuse in the driver's under-dash fuse/relay box.
  33. Jump the SCS line with the HDS.
  34. Disconnect PCM Connector B (44P).
  35. Check for continuity between PCM Connector terminal B37 and body ground.
    Fig 6: Checking Continuity Between PCM Connector Terminal B37 And Body Ground
    G04546010Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 36.

    NO  - Replace the No. 1 FUEL PUMP (15 A) fuse, and update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

  36. Remove PGM-FI main relay 2 (FUEL PUMP) (A).
    Fig 7: Removing PGM-FI Main Relay 2 (Fuel Pump)
    G04546011Courtesy of AMERICAN HONDA MOTOR CO., INC.
  37. Check for continuity between PCM Connector terminal B37 and body ground.
    Fig 8: Checking Continuity Between PCM Connector Terminal B37 And Body Ground
    G04546012Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the No. 1 FUEL PUMP (15 A) fuse and the PCM (B37), or between the No. 1 FUEL PUMP (15 A) fuse and PGM-FI main relay 2 (FUEL PUMP). Also replace the No. 1 FUEL PUMP (15 A) fuse.

    NO  - Go to step 38.

  38. Remove the driver's side second row seat (see LEFT SECOND ROW SEAT DISASSEMBLY/REASSEMBLY ).
  39. Remove the access panel from the floor.
  40. Disconnect the fuel pump 5P Connector.
  41. Check for continuity between fuel pump 5P Connector terminal No. 5 and body ground.
    Fig 9: Checking Continuity Between Fuel Pump 5P Connector Terminal No. 5 And Body Ground
    G04546013Courtesy 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. 1 FUEL PUMP (15 A) fuse.

    NO  - Go to step 42.

  42. Reinstall PGM-FI main relay 2 (FUEL PUMP) (A).
    Fig 10: Installing PGM-FI Main Relay 2 (Fuel Pump)
    G04546014Courtesy of AMERICAN HONDA MOTOR CO., INC.
  43. Check for continuity between fuel pump 5P Connector terminal No. 5 and body ground.
    Fig 11: Checking Continuity Between Fuel Pump 5P Connector Terminal No. 5 And Body Ground
    G04546015Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Replace PGM-FI main relay 2 (FUEL PUMP). Also replace the No. 1 FUEL PUMP (15 A) fuse.

    NO  - Check the fuel pump, and replace it if necessary (see FUEL PUMP CIRCUIT TROUBLESHOOTING ). Also replace the No. 1 FUEL PUMP (15 A) fuse.

  44. Jump the SCS line with the HDS.
  45. Disconnect PCM Connector A (44P) and B (44P).
  46. Turn the ignition switch ON (II).
  47. Measure voltage between PCM Connector terminal B37 and body ground.
    Fig 12: Measuring Voltage Between PCM Connector Terminal B37 And Body Ground
    G04546016Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 48.

    NO  - Repair open in the wire between the No. 1 FUEL PUMP (15 A) fuse and the PCM (B37).

  48. Measure voltage between PCM Connector terminal A6 and body ground.
    Fig 13: Measuring Voltage Between PCM Connector Terminal A6 And Body Ground
    G04546017Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  54.

    NO  - Go to step 49.

  49. Turn the ignition switch OFF.
  50. Remove PGM-FI main relay 1 (FI MAIN) (A).
    Fig 14: Removing PGM-FI Main Relay 1 (FI Main)
    G04546018Courtesy of AMERICAN HONDA MOTOR CO., INC.
  51. Measure voltage between PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 3 and body ground.
    Fig 15: Measuring Voltage Between PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 3 And Body Ground
    G04546019Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 52.

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

  52. Connect PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 4 to body ground with a jumper wire.
    Fig 16: Connecting PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 4 To Body Ground With Jumper Wire
    G04546020Courtesy of AMERICAN HONDA MOTOR CO., INC.
  53. Check for continuity between PCM Connector terminal A6 and body ground.
    Fig 17: Checking Continuity Between PCM Connector Terminal A6 And Body Ground
    G04546021Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Test PGM-FI main relay 1 (FI MAIN) (see POWER RELAY TEST ). If the relay is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). 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 (FI MAIN) and the PCM (A6).

  54. Reconnect PCM Connector A (44P).
  55. Turn the ignition switch ON (II).
  56. Measure voltage between body ground and PCM Connector terminal B3.
    Fig 18: Measuring Voltage Between Body Ground And PCM Connector Terminal B3
    G04546022Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  64.

    NO  - Go to step 57.

  57. Turn the ignition switch OFF.
  58. Remove PGM-FI main relay 1 (FI MAIN) (A).
    Fig 19: Removing PGM-FI Main Relay 1 (FI Main)
    G04546023Courtesy of AMERICAN HONDA MOTOR CO., INC.
  59. Turn the ignition switch ON (II).
  60. Measure voltage between PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 1 and body ground.
    Fig 20: Measuring Voltage Between PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 1 And Body Ground
    G04546024Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 61.

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

  61. Turn the ignition switch OFF.
  62. Connect PGM-FI main relay 1 (FI MAIN) 4P Connector terminal No. 2 to body ground with a jumper wire.
    Fig 21: Connecting PGM-FI Main Relay 1 (FI Main) 4P Connector Terminal No. 2 To Body Ground With A Jumper Wire
    G04546025Courtesy of AMERICAN HONDA MOTOR CO., INC.
  63. Check for continuity between PCM Connector terminal B3 and body ground.
    Fig 22: Checking Continuity Between PCM Connector Terminal B3 And Body Ground
    G04546026Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  - Repair open in the wire between PGM-FI main relay 1 (FI MAIN) and the PCM (B3).

  64. Turn the ignition switch OFF.
  65. Disconnect PCM Connector A, B, and C.
  66. Check for continuity between body ground and PCM Connector terminals A22, B1, B36, B43, C1, and C40 individually.
    Fig 23: Checking Continuity Between Body Ground And PCM Connector Terminals A22
    G04546027Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 24: Checking Continuity Between Body Ground And PCM Connector Terminals B1, B36 And B43
    G04546028Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 25: Checking Continuity Between Body Ground And PCM Connector Terminals C1, And C40
    G04546029Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 67.

    NO  - Repair open in the wire(s) between PCM (A22, B1, B36, B43, C1, C40) and body ground (G101).

  67. Disconnect the Connector from each of these sensors, one at a time, and check for continuity between body ground and PCM Connector terminal A19, A24, A25, B18, B19, and C13 individually.
    • MAP sensor
    • Output shaft (countershaft) speed sensor
    • EGR valve position sensor
    • Input shaft (mainshaft) speed sensor
    • APP sensor A
    • APP sensor B
    • TP sensor
    • FTP sensor
      Fig 26: Checking Continuity Between Body Ground And PCM Connector Terminal A19, A24 And A25
      G04546030Courtesy of AMERICAN HONDA MOTOR CO., INC.
      Fig 27: Checking Continuity Between Body Ground And PCM Connector Terminal B18 And B19
      G04546031Courtesy of AMERICAN HONDA MOTOR CO., INC.
      Fig 28: Checking Continuity Between Body Ground And PCM Connector Terminal C13
      G04546032Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short to ground in the wire between PCM and the following sensors.

    • MAP sensor
    • Output shaft (countershaft) speed sensor
    • EGR valve position sensor
    • Input shaft (mainshaft) speed sensor
    • APP sensor A
    • APP sensor B
    • TP sensor
    • FTP sensor

    NO  - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck (see PCM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

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