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Home >> Acura >> 2007 >> MDX >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Entertainment Systems >> HANDSFREELINK System >> Control Unit Input Test/Replacement
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Control Unit Input Test/Replacement

  1. Remove the console rear trim (see CENTER CONSOLE REAR TRIM REMOVAL/ INSTALLATION ).
  2. Disconnect the 28P connector (A) from the HandsFreeLink control unit (B).
    Fig 1: Identifying 28P Connector Terminals
    G05488748Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Inspect the connector and socket terminals for a good pinfit 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 connector, 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 5.
      TEST CONDITION

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      1 BLK Under all conditions Measure the voltage to ground: There should be less than 0.5 V.
      • Poor ground (G506)
      • An open in the wire
      15 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 5 (10 A) fuse in the driver's under-dash fuse/relay box
      • An open in the wire
      16 PUR Ignition switch ACC (I) or ON (ID Measure the voltage to ground: There should be battery voltage.
      • Blown No. 32 (10 A) fuse in the driver's under-dash fuse/relay box
      • An open in the wire
  5. Disconnect the 28P connector again, and make this input test at the connector.
    • If the test indicates a problem, find and correct the cause, then recheck the system.
    • If the input test proves OK, the HandsFreeLink control unit must be faulty, replace it.
      TEST CONDITION

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      19 LT GRN Under all conditions Check for continuity between No. 19 terminal and the driver's under-dash fuse/relay box connector X (39P) No. 27 terminal: There should be continuity. An open in the wire
      Driver's under-dash fuse/relay box connector X (39P) disconnected Check for continuity to ground: There should be no continuity. Short to ground