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Control Unit Input Test/Replacement

WARNING: This page is about a different car, the 2008 Acura TSX, 2007 Acura TSX, 2006 Acura TSX, 2005 Acura TSX, and 2004 Acura TSX. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before testing, troubleshoot the multiplex integrated control system using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Turn the ignition switch to LOCK (0).
  2. Remove the right kick panel (see FRONT DOOR SILL AREA ).
  3. Disconnect the 22P connector (A) from the Hands Freelink control unit (B).
    Fig 1: Identifying 22P Connector And Hands Freelink Control Unit
    G05489283Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Inspect the connector and socket 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 5.
  5. With the connector still disconnected, 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 6.
      POSSIBLE CAUSE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      13 BLK Under all conditions Check for continuity to ground: There should be continuity.
      • Poor ground (G503)
      • An open in the ground wire
      11 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 6 (10 A) fuse in the under-dash fuse/relay box
      • An open in the wire
      14 BLU (B-CAN) Under all conditions Check for continuity between No. 14 terminal and the under-dash fuse/relay box connector X (39P) terminal No. 18:
      There should be continuity.      		 An open in the B-CAN wire
      NOTE: Use the HDS and check for B-CAN DTCs.
      Under dash fuse relay box connector X (39P) disconnected Check for continuity to ground: There should be no continuity. A short to ground in the wire
      NOTE: Use the HDS and check for B-CAN DTCs.
      1 YEL Ignition switch ACC (I) or ON (II) Measure the voltage to ground: There should be battery voltage.
      • Blown No. 32 (7.5 A) fuse in the under-dash fuse/relay box
      • An open in the wire
  6. Turn the ignition switch to LOCK (0).
  7. Reconnect the 22P connector to the Hands Freelink control unit, and connector X (39P) to the under-dash fuse/ relay box.
  8. Turn the ignition switch ON (II), 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 input test prove OK, the Hands Freelink control unit must be faulty; replace it.
      POSSIBLE CAUSE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      2 PUR Ignition switch ACC (I) or ON (II)
      • HFL TALK and HFL BACK button not pressed: About 5 V
      • HFL TALK button pressed: About 3 V
      • HFL BACK button pressed: About 2 V
      • An open or short in the HFL button input wire (PUR or RED/BLK)
      • An open in the HFL button ground wire (BRN or GRN/BLK)
      • Open in the audio unit ground
      NOTE: Use the HDS and check for B-CAN DTCs.
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