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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 Connector Terminals Layout
    G08094831Courtesy 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 are 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
    M34 GRY Ignition key inserted into the ignition switch Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G502) or an open in the ground wire
    • Faulty ignition key switch
    • An open or high resistance in the wire
    Ignition switch in LOCK (0) position and ignition key removed from the ignition switch Measure the voltage to ground: There should be at least 5 V.
    • Faulty ignition key switch
    • A short to ground in the wire
    M8
    .
    M33    		 BLU
    .
    BLK    		 Combination light switch OFF Measure the voltage between terminals M8 and M33: There should be less than 0.2 V.
    • Faulty combination light switch
    • An open or high resistance in the wire
    Combination light switch in any other position than OFF Measure the voltage between terminals M8 and M33: There should be at least 5 V.
    • Faulty combination light switch
    • A short to ground in the wire
    M7
    .
    M33    		 GRY
    .
    BLK    		 Combination light switch (PARKING position) ON Measure the voltage between terminals M7 and M33: There should be less than 0.2 V.
    • Faulty combination light switch
    • An open or high resistance in the wire
    Combination light switch OFF Measure the voltage between terminals M7 and M33: There should be at least 5 V.
    • Faulty combination light switch
    • A short to ground in the wire
    M5
    .
    M33    		 RED
    .
    BLK    		 Combination light switch (Headlight position) ON Measure the voltage between terminals M5 and M33: There should be less than 0.2 V.
    • Faulty combination light switch
    • An open or high resistance in the wire
    Combination light switch OFF Measure the voltage between terminals M5 and M33: There should be at least 5 V.
    • Faulty combination light 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 Terminal Layout
    G08094832Courtesy 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 are 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 ignition switch
    • 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
    22 ORN Parking brake lever pulled Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty parking brake switch
    • An open or high resistance in the wire
    Parking brake lever released Measure the voltage to ground: There should be about 5 V.
    • Faulty parking brake switch
    • A short to ground in the wire
  10. Do the Gauge Control Module Self-diagnostic Function (see SELF-DIAGNOSTIC FUNCTION ), and check the beeper and the seat belt reminder indicator.
    • If the beeper sounds and the seat belt reminder indicator flashes, go to step 11.
    • If the beeper does not sound or the seat belt reminder indicator does not flash, replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).
  11. Substitute a known-good gauge control module, and recheck the system.
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