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Control Unit Input Test: MICU

  1. Turn the ignition switch OFF.
  2. Remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Disconnect the driver's under-dash fuse/relay box connectors.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Driver's Under-Dash Fuse/Relay Box Connectors
    G05497016Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
    • If the terminals look OK, go to step 5.
  5. With the connectors still disconnected, make these input tests at the connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 6.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    P8 PNK Under all conditions Attach to ground: The driver's and front passenger's foot lights should come on.
    • Blown No. 6 (7.5A) fuse in the driver's under-dash fuse/relay box
    • Faulty foot light
    • An open in the wire
    H14 ORN Under all conditions Attach to ground: The ignition key light should come on.
    • Blown No. 7 (10A) fuse in the driver's under-dash fuse/relay box
    • Faulty ignition key light
    • An open in the wire
    W4 PNK Interior lights switch in DOOR position Attach to ground: The individual map lights should come on.
    • Blown No. 6 (7.5A) fuse in the driver's under-dash fuse/relay box
    • Faulty map light
    • Faulty roof console
    • An open in the wire
  6. Reconnect the connectors to the driver's under-dash fuse/relay box, and make these input tests at the connectors.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    P1 BRN Under all conditions Measure the voltage to ground: There should be less than 0.5 V.
    • Poor ground(G502)
    • An open in the wire
    E9 BLK Under all conditions Measure the voltage to ground: There should be less than 0.5 V.
    • Poor ground (G601)
    • An open in the wire
    H9 BLK

    DRIVER'S MPCS UNIT 

  7. Turn the ignition switch OFF.
  8. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  9. Disconnect driver's MPCS unit connector A (40P).
    Fig 2: Identifying Driver's MPCS Unit Connector Terminal A (40P)
    G05497017Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
    • If the terminals look OK, go to step 11.
  11. With the connector still disconnected, make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 12.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A8 GRY Driver's under-dash fuse/relay box connector H (14P) and power window master switch 6P connector disconnected Check for continuity between the A8 terminal and driver's under-dash fuse/relay box connector H (14P) No. 4 terminal: There should be continuity. An open in the wire
    Check for continuity to ground: There should be no continuity. A short to ground in the wire
  12. Reconnect the connector to the driver's MPCS unit, turn the ignition switch ON (II), and make these tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 13.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A7 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 15 (40A) fuse in the under-hood fuse/relay box
    • Blown No. 7 (10A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    A3 GRN Driver's door open Measure the voltage to ground: There should be less than 1 V.
    • Faulty driver's door switch
    • An open in the wire
    Driver's door closed Measure the voltage to ground: There should be 5 V or more.
    • Faulty driver's door switch
    • A short to ground in the wire
    A21 BLU Driver's door key cylinder in UNLOCK Measure the voltage to ground: There should be less than 1 V.
    • Faulty driver's door key cylinder switch
    • An open in the wire
    Driver's door key cylinder in neutral or LOCK Measure the voltage to ground: There should be 5 V or more.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire

    FRONT PASSENGER'S MPCS UNIT 

  13. Turn the ignition switch OFF.
  14. Remove the front passenger's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  15. Disconnect front passenger's MPCS unit connector A (28P).
    Fig 3: Identifying Front Passenger's MPCS Unit Connector Terminal A (28P)
    G05497018Courtesy of AMERICAN HONDA MOTOR CO., INC.
  16. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
    • If the terminals look OK, go to step 17.
  17. With the connector still disconnected, make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 18.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A4 GRY Driver's under-dash fuse/relay box connector X (39P) and right rear power window switch 14P connector disconnected Check for continuity between the A4 terminal and driver's under-dash fuse/relay box connector X (39P) No. 15 terminal: There should be continuity.
    • Faulty passenger's under-dash fuse/relay box
    • An open in the wire
    Check for continuity to ground: There should be no continuity.
    • Faulty passenger's under-dash fuse/relay box
    • A short to ground in the wire
  18. Reconnect the connector to the front passenger's MPCS unit, and make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 19.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A2 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 15 (40A) fuse in the under-hood fuse/relay box
    • Blown No. 7 (10A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • Faulty passenger's under-dash fuse/relay box
    • An open in the wire
    A28 LT GRN Front passenger's door open Measure the voltage to ground: There should be less than 1 V.
    • Faulty front passenger's door switch
    • An open in the wire
    Front passenger's door closed Measure the voltage to ground: There should be 5 V or more.
    • Faulty front passenger's door switch
    • A short to ground in the wire

    LEFT REAR POWER WINDOW SWITCH 

  19. Turn the ignition switch OFF.
  20. Remove the left rear power window switch (see POWER WINDOW MASTER SWITCH REPLACEMENT ).
  21. Disconnect the 14P connector from the left rear power window switch.
    Fig 4: Identifying Left Rear Power Window Switch Connector Terminal (14P)
    G05497019Courtesy of AMERICAN HONDA MOTOR CO., INC.
  22. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
    • If the terminals look OK, go to step 23.
  23. With the connector still disconnected, make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 24.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    11(1) WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 6 (7.5A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    13(1) LT BLU Left rear door open Measure the voltage to ground: There should be less than 1 V.
    • Faulty left rear door switch
    • An open in the wire
    Left rear door closed Measure the voltage to ground: There should be 5 V or more.
    • Faulty left rear door switch
    • A short to ground in the wire
    2 GRY Driver's under-dash fuse/relay box connector J (21P) disconnected Check for continuity between the No. 2 terminal and driver's under-dash fuse/relay box connector J (21P) No. 1 terminal: There should be continuity. An open in the wire
    Check for continuity to ground: There should be no continuity. A short to ground in the wire
    (1) Reconnect the left rear power window switch 14P connector.

    RIGHT REAR POWER WINDOW SWITCH 

  24. Turn the ignition switch OFF.
  25. Remove the right rear power window switch (see POWER WINDOW MASTER SWITCH REPLACEMENT ).
  26. Disconnect the 14P connector from the right rear power window switch.
    Fig 5: Identifying Right Rear Power Window Switch Connector Terminal (14P)
    G05497020Courtesy of AMERICAN HONDA MOTOR CO., INC.
  27. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
    • If the terminals look OK, go to step 28.
  28. With the connector still disconnected, make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 29.
    POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    11(1) WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 15 (40A) fuse in the under-hood fuse/relay box
    • Blown No. 6 (7.5A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • Faulty passenger's under-dash fuse/relay box
    • An open in the wire
    13(1) LT BLU Right rear door open Measure the voltage to ground: There should be less than 1 V.
    • Faulty right rear door switch
    • An open in the wire
    Right rear door closed Measure the voltage to ground: There should be 5 V or more.
    • Faulty right rear door switch
    • A short to ground in the wire
    2 GRY Driver's under-dash fuse/relay box connector X (39P) and passenger's MPCS unit connector A (28P) disconnected Check for continuity between the No. 2 terminal and driver's under-dash fuse/relay box connector X (39P) No. 15 terminal: There should be continuity.
    • Faulty passenger's under-dash fuse/relay box
    • An open in the wire
    Check for continuity to ground: There should be no continuity.
    • Faulty passenger's under-dash fuse/relay box
    • A short to ground in the wire
    (1) Reconnect the right rear power window switch 14P connector.
  29. If multiple failures are found on more than one control unit, replace the driver's under-dash fuse/relay box (includes the MICU). If input failures are related to a particular control unit, replace the control unit.
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