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MICU Input Test

NOTE: Before testing, check for No. 22 (7.5 A) fuse in the under-dash fuse/relay box.
  1. Turn the ignition switch to LOCK (0).
  2. Remove the fuse access panel (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ).
  3. Disconnect the under-dash fuse/relay box connectors C, E, G, 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
    G05960049Courtesy 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. 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 (see REMOVAL AND INSTALLATION ).
    TEST CONDITION 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 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
    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
    W1 YEL Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 60 (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
    • Faulty driver's door switch ground
    • 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
    • Faulty front passenger's door switch ground
    • An open 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
    C40 GRN Right rear door open Measure the voltage to ground:
    There should be less than 0.2 V.
    • Faulty right rear door switch
    • Faulty right rear door switch ground
    • 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
    C26 PNK Left rear door open Measure the voltage to ground:
    There should be less than 0.2 V.
    • Faulty left rear door switch
    • Faulty left rear door switch ground
    • 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
    C22 ORN Tailgate open Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G602) or an open in the ground wire
    • Faulty tailgate latch switch
    • An open or high resistance in the wire
    Tailgate closed Measure the voltage to ground:
    There should be about 5 V or more.
    There should be no continuity
    • Faulty tailgate latch 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
    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 neutral or 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
    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 neutral or UNLOCK 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
    G7 BLU Ceiling light switch in middle position Connect terminal G7 and body ground with a jumper wire:
    The ceiling light should come on.
    • Blown No. 1 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty ceiling light
    • Blown bulb
    • An open or high resistance in the wire
    C18 PUR Under all conditions Connect terminal C18 and body ground with a jumper wire:
    The cargo area light should come on.
    • Blown No. 1 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty cargo area light
    • Blown bulb
    • An open or high resistance in the wire
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