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Control Unit Input Test

NOTE:
  • Before testing, troubleshoot the multiplex integrated control unit first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  • Before testing, do the gauge control module self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ) to make sure the beeper and the indicators in the gauge control module work properly and the F-CAN line are OK.
  • Before doing the input tests, check the No. 10 (7.5 A) fuse in the under-dash fuse/relay box.

MICU 

  1. Turn the ignition switch to LOCK (0), and remove the driver's dashboard lower cover (see INSTRUMENT PANEL REMOVAL/INSTALLATION ).
  2. Disconnect under-dash fuse/relay box connectors D, E, F, G, R, S and T.
    NOTE: All connector views are shown from wire side of female terminals.
    Fig 1: Identifying Wire Side Of Female Connector Terminal Identification
    G05966481Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. 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  4.
  4. Reconnect the connectors to the under-dash fuse/relay box, do these 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  5.
    WIRE CONDITION TABLE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    E6 BLK In all ignition switch positions Measure the voltage to ground There should be less than 0.2 V.
    • Poor ground (G401)
    • An open or high resistance in the ground wire
    F20 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 ground wire
    T34 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G401)
    • An open or high resistance in the ground wire
    D2 PNK Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Faulty ignition switch
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the ground wire
    G2 PNK Under all conditions Measure the voltage to ground. There should be battery voltage.
    • Blown No. 23 (10 A) fuse in the under-hood fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the ground wire
    E37 YEL 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 ground wire
    Driver's door closed Measure the voltage to ground: There should be at least 5 V.
    • Faulty driver's door switch
    • Faulty under-dash fuse/relay box
    • A short to ground in the wire
    R6 RED Ignition key inserted into the ignition switch Measure the voltage to ground-There should be less than 0.2V.
    • Poor ground (G401) or open in the ground wire
    • Faulty ignition key switch
    • An open or high resistance in the wire
    Ignition key removed from the ignition switch Measure the voltage to ground: There should be at least 5 V.
    • Faulty ignition key switch
    • Faulty MICU
    • A short to ground in the wire
    S1
    .
    S5    		 ORN
    .
    BLK    		 Combination light switch OFF Measure the voltage between terminals S1 and S5: There should be less than 0.2V.
    • 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 S1 and S5. There should be at least 5 V.
    • Faulty combination light switch
    • A short to ground in the wire
    • Faulty MICU
    S13
    .
    S5    		 GRY
    .
    BLK    		 Combination light switch (PARKING position) ON Measure the voltage between terminals S13 and S5: There should be less than 0.2V.
    • Faulty combination light switch
    • An open or high resistance in the wire
    Combination light switch OFF Measure the voltage between terminals S13 and S5: There should be more than 5 V.
    • Faulty combination light switch
    • A short to ground in the wire
    S11
    .
    S5    		 LT GRN
    .
    BLK    		 Combination light switch (Headlight position) ON Measure the voltage between terminals S11 and S5: There should be less than 0.2V.
    • Faulty combination light switch
    • An open or high resistance in wire
    Combination light switch OFF Measure the voltage between terminals S11 and S5: There should be at least 5 V.
    • Faulty combination light switch
    • A short to ground in the wire

    Gauge Control Module 

  5. Turn the ignition switch to LOCK (0).
  6. Remove the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ), and disconnect the 32P connector from it
    Fig 2: Identifying Gauge Control Module Connector Terminal
    G05966482Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. 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  8.
  8. Reconnect the connector to the gauge control module, 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  9.
      WIRE CONDITION TABLE

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      13 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G401)
      • An open or high resistance in the ground wire
      16 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Faulty under-dash fuse/relay box
      • An open or high resistance in the wire
      32 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
      • Faulty under-dash fuse/relay box
      • An open or high resistance in the wire
      21 BLK/YEL Parking brake pedal pressed Measure the voltage to ground: There should be less than 0.2 V.
      • Faulty parking brake switch
      • Faulty parking brake switch ground
      • An open or high resistance in the wire
      Parking brake pedal released Measure the voltage to ground: There should be at least 5 V.
      • Faulty parking brake switch
      • Faulty gauge control module
      • A short to ground in the wire
  9. If the lights-on reminder has a problem, substitute a known-good under-dash fuse/relay box, and recheck the system. If the seat belt reminder has a problem, check for SRS DTCs and check the seat belt buckle switch. If all the tests prove OK, go to step  10.
  10. Substitute a known-good gauge control module, and recheck the system
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