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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 Terminals
    G05496814Courtesy of AMERICAN HONDA MOTOR CO., INC.

    *Connector view shown rotated 180 "from actual position in the under-dash fuse/relay box.

  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.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    F5 YEL Connect battery power to F5 terminal momentarily. Check the trunk lid opener solenoid operation:
    The trunk lid should open.
    • Faulty trunk lid opener solenoid
    • An open in the wire
    P29 GRIM Connect battery power to P29 terminal momentarily. Check the keyless buzzer operation:
    The buzzer should sound.
    • Faulty keyless buzzer
    • An open in the wire
    K2 YEL Connect battery power to K2 (K12) terminal, and K12 (K2) terminal to P1 terminal. Check the door lock actuator operation.
    The driver's door lock actuator should UNLOCK (LOCK).
    • Faulty driver's door lock actuator
    • An open in the wire
    K12 BLU
    E2 BLU Connect battery power to E2(E8) terminal, and E8 (E2) terminal to P1 terminal. Check the door lock actuator operation.
    The left rear door lock actuator should LOCK (UNLOCK).
    • Faulty left rear door lock actuator
    • An open in the wire
    E8 YEL
    N7 BLU Connect battery power to N7 (N9) terminal, and N9 (N7) terminal to P1 terminal. Check the door lock actuator operation.
    The front passenger's and right rear door lock actuators should LOCK (UNLOCK).
    • Faulty front passenger's door lock actuator
    • Faulty right rear door lock actuator
    • An open in the wire
    N9 YEL
  6. Reconnect the connectors to the driver's under-dash fuse/relay box, turn the ignition switch ON (II), and 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 7.
    WIRE CAVITY 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
    P16 RN Transmission range switch in P position. Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground(G101)
    • Faulty transmission range switch
    • An open in the wire
    Transmission range switch in any other position than P. Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty transmission range switch
    • A short to ground in the wire
    Q4 BLU Trunk lid open
    NOTE: Trunk light bulb removed.
    		 Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground(G701)
    • Faulty trunk lid latch switch
    • An open in the wire
    Trunk lid closed
    NOTE: Trunk light bulb removed.
    		 Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty trunk lid latch switch
    • A short to ground in the wire
    Q8 LT BLU Trunk lid outer handle pulled Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground(G701)
    • Faulty trunk lid outer handle switch
    • An open in the wire
    Trunk lid outer handle released Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty trunk lid outer handle switch
    • A short to ground in the wire

    Driver's MPCS Unit 

  7. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  8. Disconnect driver's MPCS unit connector A(40P) and B(14P).
    Fig 2: Identifying Driver's MPCS Unit 40P And 14P Connector
    G05496815Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. 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 10.
  10. 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 11.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A23 PNK Driver's door lock switch in LOCK Check for continuity between the terminals:
    There should be continuity.
    • Faulty driver's door lock switch
    • An open in the wire
    A27 LT BLU
    A23 PNK Driver's door lock switch in neutral or UNLOCK Check for continuity between the terminals:
    There should be no continuity.
    • Faulty driver's door lock switch
    • A short to ground in the wire
    A27 LT BLU
    A24 ORN Driver's door lock switch in UNLOCK Check for continuity between the terminals:
    There should be continuity.
    • Faulty driver's door lock switch
    • An open in the wire
    A27 LT BLU
    A24 ORN Driver's door lock switch in neutral or LOCK Check for continuity between the terminals:
    There should be no continuity.
    • Faulty driver's door lock switch
    • A short to ground in the wire
    A27 LT BLU
    A4 RED Under all conditions Check for continuity between the terminals:
    There should be continuity.
    • Faulty driver's door lock switch
    • Blown bulb
    • An open in the wire
    A27 LT BLU
  11. Reconnect the connectors to the driver's MPCS unit, turn the ignition switch ON (II), and 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 12.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A5 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
    BH 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
    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
    • An open in the wire
    A25 YEL Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 21 (10A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
    A1 WHT Driver's door lock knob switch in UNLOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty driver's door lock knob switch
    • An open in the wire
    Driver's door lock knob switch in LOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door lock knob switch
    • A short to around in the wire
    A2 PUR Driver's door lock knob switch in LOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty driver's door lock knob switch
    • An open in the wire
    Driver's door lock knob switch in UNLOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    A3 GRN Driver's door open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty driver's door switch
    • An open in the wire
    Driver's door closed Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door switch
    • A short to ground in the wire
    A6 BRN Left rear door lock knob switch in UNLOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G602)
    • Faulty left rear door switch
    • An open in the wire
    Left rear door lock knob switch in LOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty left rear door switch
    • A short to around in the wire
    A21 BLU Driver's door key cylinder switch in UNLOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty driver's door key cylinder switch
    • An open in the wire
    Driver's door key cylinder switch in neutral Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    Driver's door key cylinder switch in LOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    A22 LT BLU Driver's door key cylinder switch in LOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty driver's door key cylinder switch
    • An open in the wire
    Driver's door key cylinder switch in neutral Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    Driver's door key cylinder switch in UNLOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire

    Front Passenger's MPCS Unit 

  12. Turn the ignition switch OFF, and remove the front passenger's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  13. Disconnect passenger's MPCS unit connectors A (28P) and B (14P).
    Fig 3: Identifying Passenger's MPCS Unit 28P And 14P Connectors
    G05496816Courtesy of AMERICAN HONDA MOTOR CO., INC.
  14. 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 15.
  15. 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 16.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A15 PNK Front passenger's door lock switch in LOCK Check for continuity between the terminals:
    There should be continuity.
    • Faulty front passenger's door lock switch
    • An open in the wire
    A20 LT BLU
    A15 PNK Front passenger's door lock switch in neutral or UNLOCK Check for continuity between the terminals:
    There should be no continuity.
    • Faulty front passenger's door lock switch
    • A short to ground in the wire
    A20 LT BLU
    A16 BRN Front passenger's door lock switch in UNLOCK Check for continuity between the terminals:
    There should be continuity.
    • Faulty front passenger's door lock switch
    • An open in the wire
    A20 LT BLU
    A16 BRN Front passenger's door lock switch in neutral or LOCK Check for continuity between the terminals:
    There should be no continuity.
    • Faulty front passenger's door lock switch
    • A short to ground in the wire
    A20 LT BLU
    A9 YEL Under all conditions Check for continuity between the terminals:
    There should be continuity.
    • Faulty front passenger's door lock switch
    • Blown bulb
    • An open in the wire
    A20 LT BLU
  16. Reconnect the connectors to the front passenger's MPCS unit, and 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 17.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A7 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
    B14 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
    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
    • An open in the wire
    A17 GRN Front passenger's door lock knob switch in UNLOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground(G506)
    • Faulty front passenger's door lock knob switch
    • An open in the wire
    Front passenger's door lock knob switch in LOCK Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty front passenger's door lock knob switch
    • A short to ground in the wire
    A26 BRN Right rear door lock knob switch in LOCK Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground(G651)
    • Faulty right rear door lock knob switch ? An open in the wire
    Right rear door lock knob switch in UNLOCK Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty right rear door lock knob switch
    • A short to ground in the wire
    A28 LT GRN Front passenger's door open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G506)
    • 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 

  17. Turn the ignition switch OFF, and remove the left rear power window switch (see POWER WINDOW MASTER SWITCH REPLACEMENT ).
  18. Disconnect the rear power window switch 14P connector.
    Fig 4: Identifying Rear Power Window Switch 14P Connector
    G05496817Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. 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 20.
  20. Reconnect the connector to the switch, 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 21.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    6 BLK Under all conditions Measure the voltage to ground:
    There should be less than 0.5 V.
    • Poor ground(G602)
    • An open in the wire
    14 BLK Under all conditions Measure the voltage to ground:
    There should be less than 0.5 V.
    • Poor ground (G602)
    • An open in the wire
    11 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
    • An open in the wire
    13 LT BLU Left rear door open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G506)
    • Faulty left rear door switch
    • An open in the wire
    Left rear door closed Measure the voltage to ground:
    There should be about 5 V.
    • Faulty left rear door switch
    • A short to ground in the wire

    Turn the ignition switch OFF, and right Rear Power Window Switch 

  21. Turn the ignition switch OFF, and remove the right rear power window switch (see POWER WINDOW MASTER SWITCH REPLACEMENT ).
  22. Disconnect the right rear power window switch 14P connector.
    Fig 5: Identifying Right Rear Power Window Switch 14P Connector
    G05496818Courtesy of AMERICAN HONDA MOTOR CO., INC.
  23. Inspect the connector and socket terminals to be sure they 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 24.
  24. Reconnect the connector to the switch, 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 25.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    6 BLK Under all conditions Measure the voltage to ground:
    There should be less than 0.5 V.
    • Poor ground(G651)
    • An open in the wire
    14 BLK Under all conditions Measure the voltage to ground:
    There should be less than 0.5 V.
    • Poor ground(G651)
    • An open in the wire
    11 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
    • An open in the wire
    13 LT BLU Right rear door open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G506)
    • Faulty right rear door switch
    • An open in the wire
    Right rear door closed Measure the voltage to ground:
    There should be about 5 V.
    • Faulty right rear door switch
    • A short to ground in the wire
  25. 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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