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Driver's Unit

WARNING: This page is about a different car, the 2006 Acura MDX, 2005 Acura MDX, 2004 Acura MDX, and 2003 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
  1. Remove the driver's multiplex control unit from the driver'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
      G03642328Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Make the following input tests at 22P connector B and the driver'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, one of the multiplex control units (door, driver's or passenger's) must be faulty. Substitute a known-good control unit for the one that's is most closely related to the failure, then recheck. If the symptom continues, replace the next most likely control unit until the symptom goes away.
MULTIPLEX CONTROL UNIT INPUT TEST (DRIVER'S UNIT)

Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
B11 BLK Under all conditions Check for continuity to ground:
There should be continuity.
  • Poor ground (G501)
  • An open in the wire
A12 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
  • An open in the wire
A14 Under all conditions Check for continuity to ground:
There should be continuity.
  • Poor ground (G401)
  • An open in the wire
A24 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
A13 Ignition key is inserted into the ignition switch Check for continuity to ground:
There should be continuity.
  • Faulty ignition key switch
  • An open in the wire
  • Poor ground (G401)
Ignition key removed from the ignition switch Check for continuity to ground:
There should be no continuity.
  • Faulty ignition key switch
  • Short to ground
A1 Under all conditions Attach to ground:
Ignition key light should come on.
  • Blown No. 47 (20 A) fuse in the under-hood fuse/relay box
  • Blown LED
  • An open in the wire
A15 Short the multiplex control inspection connector terminals with the special tool Check for continuity to ground:
There should be continuity.
  • Poor ground (G401)
  • Faulty driver's fuse/relay box
  • An open in the wire
Remove the special tool from the multiplex control inspection connector Check for continuity to ground:
There should be no continuity.
  • Short to ground
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