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Home >> Acura >> 2003 >> MDX Base >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Multiplex Control System >> Multiplex Control Unit Input Test >> Passenger's Unit
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Passenger's Unit

  1. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box.
  2. 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 3.
      Fig 1: Inspecting Connector And Socket Terminals
      G03642326Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Make the following input tests at the 22P connector B and the passenger's under-dash fuse/relay box socket connector A.

    Be careful not to spread the fuse box connectors.

    • 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 1 in DOOR UNIT  .
    MULTIPLEX CONTROL UNIT INPUT TEST (PASSENGER'S UNIT)

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    B22 BLK Under all conditions Check for continuity to ground:
    There should be continuity.
    • Poor ground (G503)
    • An open in the wire
    A24 Fuse/relay box socket Under all conditions Check for voltage to ground:
    There should be battery voltage.
    • Blown No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box
    • Blown No. 54 (40 A) fuse in the under-hood fuse/relay box
    • Faulty passenger's under-dash fuse/relay box
    A8 Under all conditions Check for continuity to ground:
    There should be continuity.
    • Poor ground (G651)
    • An open in the wire
    A22 Ignition switch ON (II) Check for voltage to ground:
    There should be battery voltage.
    • Blown No. 9 (10 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
    A12 Under all conditions Attach A12 to battery voltage:
    Power window relay should click.
    Check voltage between No. 7 (20 A) passenger's fuse and ground:
    There should be battery voltage.
    • Poor ground (G651)
    • Faulty passenger's fuse box
    • Faulty power window relay
    • An open in the wire
    • Blown No. 51 (40 A) fuse in the under-hood fuse/relay box