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Control Unit Input Test

  1. Remove the HandsFreeLink control unit (see HANDSFREELINK CONTROL UNIT REMOVAL/INSTALLATION  ).
  2. Inspect the connector (A) and socket (B) terminals for a good pin fit 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: Identifying Connector And Socket Of Control Unit
      G08054348Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. 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 4.
    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    1 BLK Under all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G506)
    • An open in the wire
    15 WHT Under all ignition switch positions 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 or high resistance in the wire
    16 PUR Ignition switch ACCESSORY (I) or ON (II) 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 or high resistance in the wire
  4. Disconnect the 28P connector again, and make this input test at the connector.
    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    18 LT GRN Under all ignition switch positions Check for continuity between terminal No. 18 and under-dash fuse/relay box connector N (45P) terminal No. 28: There should be continuity.
    • An open in the wire
    • Check for CAN DTCs
    Under-dash fuse/relay box connector N (45P) disconnected Check for continuity to ground: There should be no continuity.
    • Short to ground
    • Check for CAN DTCs