2005 Acura TL AutomaticFACTORY OEM SERVICE PROCEDURE

Display and Control Unit Input Test

NOTE: Before troubleshooting, do the B-CAN system test mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ) and the display panel control unit self-diagnostic function test (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Remove the audio-HVAC display module assembly (see AUDIO-HVAC DISPLAY MODULE ASSEMBLY REMOVAL/INSTALLATION  ).
    Fig 1: Identifying Audio-HVAC Display Module Assembly Connector And Socket Terminals
    G03662469Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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.
  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.
    DISPLAY AND CONTROL UNIT INPUT TEST

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    A1 BLK Under all conditions Check for voltage to ground: There should be less than 1 V.
    • Poor ground (G501)
    • An open in the wire
    A5 YEL/RED Ignition switch ACC(I) Check for voltage to ground: There should be battery voltage.
    • Blown No. 32 (7.5A) fuse in the under-dash fuse/relay box
    • An open in the wire
    A6 WHT/RED Under all conditions Check for voltage to ground: There should be battery voltage.
    • Blown No. 7 (7.5 A) fuse in the under-dash fuse/relay box
    • An open in the wire
    A4 RED/BLK Combination light switch ON Check for voltage to ground: There should be battery voltage.
    • Faulty interior light circuit
    • An open in the wire
  4. Disconnect the 14P connector from the control unit, 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 navigation system (see SYSTEM DESCRIPTION ) and climate control (see GENERAL TROUBLESHOOTING INFORMATION ). If the navigation system and climate control system are OK, replace the display panel control unit.
    DISPLAY AND CONTROL UNIT INPUT TEST

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    A2 RED Under all conditions Check for continuity between the A2 terminal and gauge control module B9 terminal: There should be continuity. An open in the wire
    A7 RED/BLU Under all conditions Check for continuity between the A7 terminal and gauge control module B8 terminal: There should be continuity. An open in the wire
    A3 BLU Under all conditions Check for continuity between the A3 terminal and audio unit C13 terminal: There should be continuity. An open in the wire
    A8 BLU/WHT Under all conditions Check for continuity between the A8 terminal and audio unit C9 terminal: There should be continuity. An open in the wire
    A9 GRN/ORN Under all conditions Check for continuity between the A9 terminal and audio unit C8 terminal: There should be continuity. An open in the wire
    A10 WHT Under all conditions Check for continuity to ground: There should be continuity. An open in the wire
    A11 RED Under all conditions Check for continuity between the A11 terminal and audio unit C26 terminal: There should be continuity. An open in the wire
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