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Home >> Honda >> 2004 >> Odyssey EX >> Repair and Diagnosis >> Accessories & Equipment >> Interior/Illumination Lights >> Interior Lights >> Entry Lights Control System >> Control Unit Input Test
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Control Unit Input Test

  1. Before testing the entry light control functions, troubleshoot the multiplex control system (see TROUBLESHOOTING ).

    Driver's Multiplex Control Unit 

  2. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
  3. 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 4.
    Fig 1: Identifying Driver's Under-Dash Fuse/Relay Box Socket
    G01557988Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Identifying Driver's Multiplex Control Unit Connector B
    G01557989Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Identifying Driver's Under-Dash Fuse/Relay Box Connector A
    G01557990Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 4: Identifying Driver's Under-Dash Fuse/Relay Box Connector O
    G01557991Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. With the driver's unit still disconnected, make these input tests at the connector and fuse/relay box socket.
    • 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 5.
    Fig 5: Control Unit Input Test Chart
    G01557992Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Reconnect the driver's multiplex control unit to the fuse/relay box, and perform the following input tests at the appropriate connectors on the back of the 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 6.
    Fig 6: Control Unit Input Test Chart
    G01557993Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Passenger's Multiplex Control Unit 

  6. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box, and disconnect its connector.
  7. 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 8.
    Fig 7: Inspecting Connector & Socket Terminals (1 Of 2)
    G01557994Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 8: Inspecting Connector & Socket Terminals (2 Of 2)
    G01557995Courtesy of AMERICAN HONDA MOTOR CO., INC.
  8. With the control unit still disconnected, make these input tests at the connector and fuse/relay box socket.
    • 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 9.
    Fig 9: Control Unit Input Test Chart
    G01557996Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Reconnect the passenger's multiplex control unit to the fuse/relay box, and perform the following input tests at the appropriate connectors on the back of the 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 10.
    Fig 10: Control Unit Input Test Chart
    G01557997Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Door Multiplex Control Unit 

  10. Remove the driver's door panel and disconnect the 20P connector A from the door multiplex control unit.
  11. Inspect all connector and socket terminals to be sure they are 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 12.
    Fig 11: Inspecting All Connector & Socket Terminals
    G01557998Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. Reconnect the connectors to the door unit, and make the input test at the connector.
    • If a test indicates a problem, find and correct the cause, then recheck the system.
    • If the input test proves OK, go to step 13.
    Fig 12: Reconnecting Connectors To Door Unit Chart
    G01557999Courtesy of AMERICAN HONDA MOTOR CO., INC.
  13. If all the input tests prove OK, one of the control units must be faulty. Substitute a known-good control unit for the one that is most likely at fault, then recheck the system. If the system works properly, the original control unit is faulty; replace it. If there is still a malfunction, substitute a known-good control unit for the next unit most likely to be at fault, and recheck. If the system works properly, the original unit is faulty; replace it.
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