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Control Unit Input Test

  1. Before testing, troubleshoot the multiplex control system (see MULTIPLEX CONTROL SYSTEM (HATCHBACK) ).
  2. Remove the dashboard lower cover.
  3. Disconnect the under-dash fuse/relay box connectors.
    NOTE: All connectors are wire side of female terminals.
    Fig 1: Identifying Control Unit Connector Terminals
    G01400918Courtesy 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 all connections to the under-dash fuse/relay box, turn the ignition switch ON (II) to keep the system awake 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.
    Fig 2: Control Unit Input Test (Connectors Connected)
    G01400919Courtesy of AMERICAN HONDA MOTOR CO., INC.
  6. Disconnect the M, P, K and J connectors from the under-dash fuse/relay box, and make these input tests at the connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the multiplex control unit must be faulty. Replace the under-dash fuse/relay box assembly.
    Fig 3: Control Unit Input Test (M, P, K & J Connectors Disconnected)
    G01400920Courtesy of AMERICAN HONDA MOTOR CO., INC.
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