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Automatic Lighting Control Unit Input Test

WARNING: This page is about a different car, the 2008 Acura TL and 2007 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.
  1. Before testing the automatic lighting control functions, troubleshoot the multiplex integrated control system using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  2. Remove the driver's dashboard lower cover (see DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION ).
  3. Disconnect the 14P connector (A) from the automatic lighting control unit (B).
    Fig 1: Identifying Automatic Lighting Control Unit And 14P Connector
    G05462675Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. 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 5.
  5. Reconnect the automatic lighting control unit connector, then 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 inputs test prove OK, go to step 6.
    WIRE TEST CONDITION REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    8 BLK Under all conditions Measure the voltage to ground: There should be less than 0.5 V.
    • Poor ground (G501)
    • An open in the wire
    9
    1 BLK/YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. 30 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • Faulty IG2 cut relay (A/T)
    • A short to ground in the wire
    • An open in the wire
    7 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. 21 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • A short to ground in the wire
    • An open in the wire
    2 WHT Ignition switch ON (II) and headlight switch ON Measure the voltage to ground: There should be less than 1 V. An open in the wire
    4 LT GRN Disconnect under-dash fuse/relay box connector X (39P) Check for continuity between the No. 4 terminal and under-dash fuse/relay box connector X (39P) No. 27 terminal: There should be continuity. An open in the wire
    Check for continuity to ground: There should be no continuity. A short to ground in the wire
  6. Connect a voltmeter and jumper wires as shown, then turn the ignition switch ON (II) and make the input test at the connector.
    • If test indicates a problem, find and correct the cause, then recheck the system.
    • If the input test proves OK, replace the automatic lighting control unit.
      Fig 2: Connecting Voltmeter And Jumper Wires
      G05462676Courtesy of AMERICAN HONDA MOTOR CO., INC.
    WIRE TEST CONDITION REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    6 RED Cover the automatic lighting sensor. (Cut the light off completely with a dark cloth.) Measure the voltage between the No. 6 terminal and body ground: There should be less than 1 V.
    • Faulty automatic lighting sensor
    • An open in the wire
    Shine light on the automatic lighting sensor. Measure the voltage between the No. 6 terminal and body ground: There should be 5 V or more.
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