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Home >> Acura >> 2004 >> TL Standard >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Interior/Illumination Lights >> Entry Lights Control System >> Control Unit Input Test
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Control Unit Input Test

NOTE: Make sure the ignition switch is OFF before disconnecting the underdash fuse/relay box connectors.
  1. Before testing the entry light 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 ), and the keyless receiver unit input test (see KEYLESS RECEIVER UNIT INPUT TEST ).

    Multiplex Integrated Control Unit 

  2. Remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Disconnect the underdash fuse/relay box connectors.
    NOTE: All connectors are wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors And Terminals
    G03662160Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Inspect the connector 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. With the connectors still disconnected, make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, the recheck the system.
    • If all the input tests prove OK, go to step 6.
    CONTROL UNIT INPUT TEST - MULTIPLEX INTEGRATED CONTROL UNIT

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    P1 BLK Under all conditions Check for continuity to ground:
    There should be continuity.
    • Poor ground (G502)
    • An open in the wire
    E9 BLK Under all conditions Check for continuity to ground:
    There should be continuity.
    • Poor ground (G503, G601)
    • An open in the wire
    P7 WHT/BLK Under all conditions Attach to ground:
    Ignition key light should come on.
    • Blown No. 6 (7.5 A) fuse in the underdash fuse/relay box
    • Faulty ignition key light (LED)
    • An open in the wire
    W4 GRN/RED Interior light switch in middle (DOOR) position Attach to ground:
    Front and rear map light(s) should come on.
    • Blown No. 6 (7.5 A) fuse in the underdash fuse/relay box
    • Blown bulb
    • Faulty map light
    • An open in the wire
  6. Reconnect the connectors to the underdash fuse/relay box. Turn the ignition switch ON (II), and make these input tests at the appropriate connectors on the underdash fuse/relay box.
    • 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 7.
    CONTROL UNIT INPUT TEST - MULTIPLEX INTEGRATED CONTROL UNIT

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    E15 GRN Driver's door open Check for voltage to ground:
    There should be less than 1 V.
    • Faulty driver's door switch
    • An open in the wire
    Driver's door closed Check for voltage to ground:
    There should be 5 V or more.
    • Faulty driver's door switch
    • Short to ground
    H12 LT GRN/RED Front passenger's door open Check for voltage to ground:
    There should be less than 1 V.
    • Faulty front passenger's door switch
    • An open in the wire
    Front passenger's door closed Check for voltage to ground:
    There should be 5 V or more.
    • Faulty front passenger's door switch
    • Short to ground
    E14 GRN/YEL Left rear door open Check for voltage to ground:
    There should be less than 1 V.
    • Faulty left rear door switch
    • An open in the wire
    Left rear door closed Check for voltage to ground:
    There should be 5 V or more.
    • Faulty left rear door switch
    • Short to ground
    H13 GRN/WHT Right rear door open Check for voltage to ground:
    There should be less than 1 V.
    • Faulty right rear door switch
    • An open in the wire
    Right rear door closed Check for voltage to ground:
    There should be 5 V or more.
    • Faulty right rear door switch
    • Short to ground
    P13 RED/WHT Ignition key inserted into the ignition switch Check for voltage to ground:
    There should be less than 1 V.
    • Poor ground (G501)
    • Faulty ignition key switch
    • An open in the wire
    Ignition switch OFF and the ignition key removed from the ignition switch Check for voltage to ground:
    There should be 5 V or more.
    • Faulty ignition key switch
    • Short to ground

    Door Multiplex Control Unit 

  7. Turn the ignition switch OFF.
  8. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  9. Disconnect the 22P connector from the door multiplex control unit.
  10. 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 11.
    Fig 2: Identifying Door Multiplex Control Unit 22P Connector
    G03662161Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Reconnect the connector to the door multiplex control unit. Turn the ignition switch ON (II), and make these input tests at the appropriate connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the MICU must be faulty; replace the underdash fuse/relay box.
    CONTROL UNIT INPUT TEST - DOOR MULTIPLEX CONTROL UNIT

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    A19 WHT/RED Driver's door key cylinder switch in LOCK Check for voltage to ground:
    There should be less than 1 V.
    • Faulty driver's door key cylinder switch
    • Poor ground (G503, G601)
    • An open in the wire
    • Short to ground
    Driver's door key cylinder switch in the neutral position Check for voltage to ground:
    There should be 5 V or more.
    Driver's door key cylinder switch in UNLOCK Check for voltage to ground: There should be 5 V or more.
    A18 WHT Driver's door key cylinder switch in UNLOCK Check for voltage to ground:
    There should be less than 1 V.
    • Faulty driver's door key cylinder switch
    • Poor ground (G503, G601)
    • An open in the wire
    • Short to ground
    Driver's door key cylinder switch in the neutral position Check for voltage to ground:
    There should be 5 V or more.
    Driver's door key cylinder switch in LOCK Check for voltage to ground:
    There should be 5 V or more.
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