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MICU Input Test

NOTE:
  • Before testing, check the No. 1 (10 A), No. 20 (15 A), No. 22 (7.5 A), No. 27 (30 A), No. 35 (10 A), No. 36 (15 A), No. 38 (15A), No. 49 (15 A), No. 50 (15 A), and No. 60 (50 A) fuses in the under-dash fuse/relay box.
  • There are two pairs of fuses in the same circuit (No. 35 and No. 49 fuses, No. 36 and No. 50 fuses). If one of the fuses is blown, check the another fuse in the same circuit. If necessary, replace the damaged fuse(s).
  1. Turn the ignition switch to LOCK (0).
  2. Remove the fuse access panel (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ).
  3. Disconnect under-dash fuse/relay box connectors A, B, C, E, F, K, M, N, Q, and W.
    NOTE: All connector views are shown from wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors A, B, C, E, F, K, M, N, Q & W
    G05959956Courtesy 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, do these input tests at the following 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.
    MICU INPUT TEST REFERENCE TABLE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    E6 LT GRN Connect the battery positive terminal to terminal E6(F2), and terminal F2(E6) to body ground Check actuator operation: The driver's door lock actuator should unlock (or lock).
    • Faulty driver's door lock actuator
    • An open or high resistance in the wire
    F2 PNK
    K5 LT BLU Connect the battery positive terminal to terminal K5 (K6), and terminal K6(K5) to body ground Check actuator operation: The front passenger's door lock actuator should lock (or unlock).
    • Faulty front passenger's door lock actuator
    • An open or high resistance in the wire
    K6 YEL
    C35 PNK Connect the battery positive terminal to terminal C35 (C36), and terminal C36 (C35) to body ground Check actuator operation: The left rear door lock actuator should lock (or unlock).
    • Faulty left rear door lock actuator
    • An open or high resistance in the wire
    C36 YEL
    C47 LT BLU Connect the battery positive terminal to terminal C47 (C48), and terminal C48 (C47) to body ground Check actuator operation: The right rear door lock actuator and the tailgate lock actuator should lock (or unlock).
    • Faulty right rear door lock actuator
    • Faulty tailgate lock actuator
    • An open or high resistance in the wire
    C48 YEL
    A13() GRN Under all conditions Connect terminal A13 and terminal B23 with a jumper wire: The horn should sound
    • Faulty security horn
    • An open or high resistance in the wire
    • Poor ground
    (1) With security
  6. Reconnect the connectors to the under-dash fuse/relay box, and do these input tests at the following connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the MICU must be faulty; replace the under-dash fuse/relay box:
    MICU INPUT TEST REFERENCE TABLE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    K10 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G502) or an open in the ground wire
    • An open or high resistance in the wire
    Q9 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G502) or an open in the ground wire
    • An open or high resistance in the wire
    M16 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • An open or high resistance in the wire
    N2 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • An open or high resistance in the wire
    M23(1) GRN Under all conditions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G503) or an open in the ground wire
    • Faulty audio unit
    • An open or high resistance in the wire
    B23 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 3 (20 A) fuse in the battery terminal fuse box
    • An open or high resistance in the wire
    W1 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. 1 (100 A) fuse in the battery terminal fuse box
    • Blown No. 60 (IGN) (50 A) fuse in the under-dash fuse/ relay box
    • Faulty ignition switch
    • An open or high resistance in the wire
    C33 BLU Driver's door open Measure the voltage to ground: There should be less than 0.2 V.
    • 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 about 5 V or more.
    • Faulty driver's door switch
    • A short to ground in the wire
    C32 LT GRN Front passenger's door open Measure the voltage to ground: There should be less than 0.2 V.
    • 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 about 5 V or more.
    • Faulty front passenger's door switch
    • A short to ground in the wire
    C26 PNK Left rear door open Measure the voltage to ground: There should be less than 0.2 V.
    • 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 about 5 V or more.
    • Faulty left rear door switch
    • A short to ground in the wire
    C40 GRN Right rear door open Measure the voltage to ground: There should be less than 0.2 V.
    • 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 about 5 V or more.
    • Faulty right rear door switch
    • A short to ground in the wire
    C22 ORN Tailgate open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty tailgate latch switch
    • Poor ground (G602) or an open in the ground wire
    • An open or high resistance in the wire
    Tailgate closed Measure the voltage to ground: There should be about 5 V or more.
    • Faulty tailgate latch switch
    • A short to ground in the wire
    A29(1) PUR Hood open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty hood switch
    • Poor ground (G401) or an open in the ground wire
    • An open or high resistance in the wire
    Hood closed Measure the voltage to ground: There should be about 5 V or more.
    • Faulty hood switch
    • A short to ground in the wire
    E9 RED Driver's door lock knob switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) 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 about 5 V or more.
    • Faulty driver's door switch lock knob switch
    • A short to ground in the wire
    E2 BRN Driver's door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) 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 about 5 V or more.
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    M24 PUR Front passenger's door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G502) 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 about 5 V or more.
    • Faulty front passenger's door lock knob switch
    • A short to ground in the wire
    C45 WHT 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 lock knob 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 about 5 V or more.
    • Faulty left rear door lock knob switch
    • A short to ground in the wire
    C46 GRN Right rear door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G603) 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 about 5 V or more.
    • Faulty right rear door lock knob switch
    • A short to ground in the wire
    M34 GRY Ignition key inserted into the ignition switch Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • Faulty ignition key switch
    • An open or high resistance in the wire
    Ignition switch LOCK (0), and the ignition key removed from the ignition switch Measure the voltage to ground: There should be about 5 V or more.
    • Faulty ignition key switch
    • A short to ground in the wire
    E3(1) PUR Driver's door key cylinder switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) 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 or UNLOCK Measure the voltage to ground: There should be about 5 V or more.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    E4 GRN Driver's door key cylinder switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) 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 or LOCK Measure the voltage to ground: There should be about 5 V or more.
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    E8 LT BLU Driver's door lock switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • Faulty door lock switch
    • An open or high resistance in the wire
    Driver's door lock switch in neutral or UNLOCK Measure the voltage to ground: There should be about 5 V or more.
    • Faulty door lock switch
    • A short to ground in the wire
    E1 GRY Driver's door lock switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • Faulty door lock switch
    • An open or high resistance in the wire
    Driver's door lock switch in neutral or LOCK Measure the voltage to ground: There should be about 5 V or more.
    • Faulty door lock switch
    • A short to ground in the wire
    (1) With security
    (2) With driver's door lock switch
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