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Control Unit Input Test

MICU 

  1. Turn the ignition switch to LOCK (0).
  2. Remove the left kick panel. See TRIM REMOVAL/INSTALLATION - DOOR AREAS .
  3. Disconnect driver's under-dash fuse/relay box connectors E, F, K, N, P, and Q.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Driver's Under-Dash Fuse/Relay Box Connectors
    G07354885Courtesy 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, do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      F5 YEL Connect battery power to terminal F5 momentarily. Check the trunk lid opener solenoid operation:
      The trunk lid should open.
      • Faulty trunk lid opener solenoid
      • An open or high resistance in the wire
      • Poor ground (G701) or an open in the ground wire
      P29 GRN Connect battery power to terminal P29 momentarily. Check the keyless buzzer operation:
      The buzzer should sound.
      • Faulty keyless buzzer
      • An open or high resistance in the wire
      • Poor ground (G701) or an open in the ground wire
      K2 YEL Connect battery power to terminal K2 (K12), and terminal K12 (K2) to terminal P1. Check the door lock actuator operation:
      The driver's door lock actuator should UNLOCK (LOCK).
      • Faulty driver's door lock actuator
      • An open or high resistance in the wire
      K12 BLU
      E2 BLU Connect battery power to terminal E2 (E8), and terminal E8 (E2) to terminal P1. Check the door lock actuator operation:
      The left rear door lock actuator should LOCK (UNLOCK).
      • Faulty left rear door lock actuator
      • An open or high resistance in the wire
      E8 YEL
      N7 BLU Connect battery power to terminal N7(N9), and terminal N9(N7)to terminal P1. 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 or high resistance in the wire
      N9 YEL
  6. Reconnect the connectors to the driver's under-dash fuse/relay box, turn the ignition switch to ON (II), and do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      P1 BRN In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G502)
      • An open or high resistance in the ground wire
      E9 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601)
      • An open or high resistance in the ground wire
      P16 GRN Transmission range switch in P position. Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G101) or an open in the ground wire
      • Faulty transmission range switch
      • An open or high resistance in the wire
      Transmission range switch in any other position than P. Measure the voltage to ground:
      There should be at least 5 V.
      • 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 0.2 V.
      • Poor ground (G701) or an open in the ground wire
      • Faulty trunk lid latch switch
      • An open or high resistance in the wire
      Trunk lid closed
      NOTE: Trunk light bulb removed.
      		 Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty trunk lid latch 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 connectors A (40P) and B (14P).
    Fig 2: Identifying Driver's MPCS Unit Connectors A (40P) And B (14P)
    G07354886Courtesy 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, do the following input tests.
    • 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.
      TEST CONDITION AND WIRE 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 or high resistance 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 or high resistance 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 or high resistance in the wire
      A27 LT BLU
  11. Reconnect the connectors to the driver's MPCS unit, turn the ignition switch to ON (II), and do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      A5 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601)
      • An open or high resistance in the ground wire
      B14 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601)
      • An open or high resistance in the ground wire
      A7 WHT Under all conditions Measure the voltage to ground:
      There should be battery voltage.
      • Blown No. 15 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 7 (10 A) fuse in the driver's under-dash fuse/relay box
      • An open or high resistance in the wire
      A25 YEL Ignition switch ON (II) Measure the voltage to ground:
      There should be battery voltage.
      • Blown No. 21 (10 A) fuse in the driver's under-dash fuse/relay box
      • An open or high resistance in the wire
      A1 WHT Driver's door lock knob switch in UNLOCK Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty driver's door lock knob switch
      • An open or high resistance in the wire
      Driver's door lock knob switch in LOCK Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty driver's door lock knob switch
      • A short to ground in the wire
      A2 PUR Driver's door lock knob switch in LOCK Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty driver's door lock knob switch
      • An open or high resistance in the wire
      Driver's door lock knob switch in UNLOCK Measure the voltage to ground:
      There should be at least 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 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty driver's door switch
      • An open or high resistance in the wire
      Driver's door closed Measure the voltage to ground:
      There should be at least 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 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty left rear door switch
      • An open or high resistance in the wire
      Left rear door lock knob switch in LOCK Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty left rear door switch
      • A short to ground in the wire
      A21 BLU Driver's door key cylinder switch in UNLOCK Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty driver's door key cylinder switch
      • An open or high resistance in the wire
      Driver's door key cylinder switch in neutral Measure the voltage to ground:
      There should be at least 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 at least 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 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty driver's door key cylinder switch
      • An open or high resistance in the wire
      Driver's door key cylinder switch in neutral Measure the voltage to ground:
      There should be at least 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 at least 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 to LOCK (0), 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: Disconnecting Passenger's MPCS Unit Connectors (28P) And B (14P)
    G07354887Courtesy 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, do the following input tests.
    • 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.
      TEST CONDITION AND WIRE 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 or high resistance 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 or high resistance 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
      A1 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 or high resistance in the wire
      A20 LT BLU
  16. Reconnect the connectors to the front passenger's MPCS unit, and do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      A7 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G506)
      • An open or high resistance in the ground wire
      B14 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G506)
      • An open or high resistance in the ground wire
      A2 WHT Under all conditions Measure the voltage to ground:
      There should be battery voltage.
      • Blown No. 15 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 7 (10 A) fuse in the driver's under-dash fuse/relay box
      • An open or high resistance in the wire
      A17 GRN Front passenger's door lock knob switch in UNLOCK Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G506) or an open in the ground wire
      • Faulty front passenger's door lock knob switch
      • An open or high resistance in the wire
      Front passenger's door lock knob switch in LOCK Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty front passenger's door lock knob switch
      • A short to ground in the wire
      A26 BRN Right rear door lock knob switch in UNLOCK Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G651) or an open in the ground wire
      • Faulty right rear door lock knob switch
      • An open or high resistance in the wire
      Right rear door lock knob switch in LOCK Measure the voltage to ground:
      There should be at least 5 V.
      • 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 0.2 V.
      • Poor ground (G506) or an open in the ground wire
      • Faulty front passenger's door switch
      • An open or high resistance in the wire
      Front passenger's door closed Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty front passenger's door switch
      • A short to ground in the wire

    Left Rear Power Window Switch 

  17. Turn the ignition switch to LOCK (0), and remove the left rear power window switch. See POWER WINDOW MASTER SWITCH REPLACEMENT .
  18. Disconnect the left rear power window switch 14P connector.
    Fig 4: Disconnecting Left Rear Power Window Switch 14P Connector
    G07354888Courtesy 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 do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      6 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601)
      • An open or high resistance in the ground wire
      14 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601)
      • An open or high resistance in the ground wire
      11 WHT Under all conditions Measure the voltage to ground:
      There should be battery voltage.
      • Blown No. 15 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 6 (7.5 A) fuse in the driver's under-dash fuse/relay box
      • An open or high resistance in the wire
      13 LT BLU Left rear door open Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G601) or an open in the ground wire
      • Faulty left rear door switch
      • An open or high resistance in the wire
      Left rear door closed Measure the voltage to ground:
      There should be at least 5 V.
      • Faulty left rear door switch
      • A short to ground in the wire

    Right Rear Power Window Switch 

  21. Turn the ignition switch to LOCK (0), 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: Disconnecting Right Rear Power Window Switch 14P Connector
    G07354889Courtesy 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 do the following input tests.
    • 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.
      TEST CONDITION AND WIRE REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      6 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G651)
      • An open or high resistance in the ground wire
      14 BLK In all ignition switch positions Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G651)
      • An open or high resistance in the ground wire
      11 WHT Under all conditions Measure the voltage to ground:
      There should be battery voltage.
      • Blown No. 15 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 6 (7.5 A) fuse in the driver's under-dash fuse/relay box
      • An open or high resistance in the wire
      13 LT BLU Right rear door open Measure the voltage to ground:
      There should be less than 0.2 V.
      • Poor ground (G651) or an open in the ground wire
      • Faulty right rear door switch
      • An open or high resistance in the wire
      Right rear door closed Measure the voltage to ground:
      There should be at least 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). See DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL/INSTALLATION . If input failures are related to a particular control unit, replace the control unit.
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