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Control Unit Input Test: MICU

  1. Turn the ignition switch to LOCK (0).
  2. Remove the fuse access panel (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ), and remove the driver's dashboard lower cover (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ).
  3. Disconnect under-dash fuse/relay box connectors C, K, M, N, Q, and W.
    NOTE: All connector views are shown from wire side of female terminals.
    Fig 1: Under-Dash Fuse/Relay Box Connectors Terminals Layout
    G08094825Courtesy 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, 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  6.
      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)
      • 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(G502)
      • 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)
      • 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(G501)
      • 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 GRY 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 at least 5 V.
      • 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 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
      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 at least 5 V.
      • 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 at least 5 V.
      • Faulty left rear door switch
      • A short to ground in the wire
      C22 ORN Hatch open Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G801) or an open in the ground wire
      • Faulty hatch latch switch
      • An open or high resistance in the wire
      Hatch closed Measure the voltage to ground: There should be at least 5 V.
      • Faulty hatch latch switch
      • A short to ground in the wire

    Gauge control module 

  6. Turn the ignition switch to LOCK (0).
  7. Remove the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ), and disconnect the 32P connector from it.
    Fig 2: Gauge Control Module 32P Connector Terminals Layout
    G08094826Courtesy of AMERICAN HONDA MOTOR CO., INC.
  8. 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 9.
  9. Reconnect the connector to the gauge control module, 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  10.
      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      1 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground(G501)
      • An open or high resistance in the wire
      5 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground(G501)
      • An open or high resistance in the wire
      15 LT BLU Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
      • Blown No. 22 (7.5 A) fuse in the under-dash fuse/relay box
      • Faulty under-dash fuse/relay box
      • An open or high resistance in the wire
      16 PNK Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 1 (15 A) fuse in the under-dash fuse/relay box
      • An open or high resistance in the wire
  10. Substitute a known-good gauge control module, and recheck the system.