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Control Unit Input Test

NOTE: Before troubleshooting the safety indicator system, troubleshoot the multiplex integrated control system first using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Multiplex Integrated Control Unit 

  1. Turn the ignition switch OFF.
  2. Remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Disconnect the under-dash fuse/relay box connectors E, H and Q (see ).
    Fig 1: Identifying Wire Side Of Female Terminal
    G03691221Courtesy 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. Turn the ignition switch ON (II) and make these input tests at the appropriate connectors on the under-dash fuse/relay box.
    • 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.
      TEST POSSIBLE CAUSE (1 OF 2)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      E15 GRN Driver's door open Check for voltage to ground:
      There should be less than 1 V.
      • Faulty driver's door switch
      • An open in the wire
      Driver's door closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty driver's door switch
      • Short to ground
      H12 LT GRN/RED Front passenger's door open Check for voltage to ground:
      There should be less than 1 V.
      • Faulty front passenger's door switch
      • An open in the wire
      Front passenger's door closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty front passenger's door switch
      • Short to ground
      E14 GRN/YEL Left rear door open Check for voltage to ground:
      There should be less than 1 V.
      • Faulty left rear door switch
      • An open in the wire
      Left rear door closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty left rear door switch
      • Short to ground
      H13 GRN/WHT Right rear door open Check for voltage to ground:
      There should be less than 1 V.
      • Faulty right rear door switch
      • An open in the wire
      Right rear door closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty right rear door switch
      • Short to ground
      Q7 BLU/YEL In-bed trunk lid open Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground(G601)
      • Faulty in-bed trunk lid latch switch
      • An open in the wire
      In-bed trunk lid closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty in-bed trunk lid latch switch
      • Short to ground
      Q11 BLU/ORN Tailgate open Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G602)
      • Faulty tailgate switch
      • An open in the wire
      Tailgate closed Check for voltage to ground:
      There should be 5 V or more.
      • Faulty tailgate switch
      • Short to ground

    6. Gauge Control Module 

  6. Turn the ignition switch OFF.
  7. Remove the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).
  8. Disconnect the gauge control module connectors A (20P) and C (20P).
    Fig 2: Identifying Gauge Control Module Connector
    G03691222Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. 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 10.
  10. Reconnect the connectors to the gauge control module, turn the ignition switch ON (II), and make these input tests at the connector.
    • 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  11.
    TEST POSSIBLE CAUSE (2 OF 2)

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    A20 YEL Ignition switch ON (II) Check for voltage to ground:
    There should be battery voltage.
    • Blown No. 21 (7.5 A) fuse in the under-dash fuse/relay box
    • An open in the wire
    A19 WHT/RED Under all conditions Check for voltage to ground:
    There should be battery voltage.
    • Blown No. 7 (7.5 A) fuse in the under-dash fuse/relay box
    • An open in the wire
    A10 BLK Under all conditions Check for voltage to ground:
    There should be battery voltage.
    • Poor ground (G401)
    • An open in the wire
    C10 BLK Under all conditions Check for voltage to ground:
    There should be less than 1 V,
    • Poor ground (G402)
    • An open in the wire
  11. If all the input tests prove OK, and no DTCs were found during MICS troubleshooting (B-CAN System Diagnostic Test Mode A), go to the B-CAN system input and output index (see B-CAN SYSTEM UNIT INPUT/OUTPUT DEVICE CONTROL ). If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU). If input failures are related to particular control unit, replace the control unit.
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