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Control Circuit Input Test

WARNING: This page is about a different car, the 2008 Honda Pilot, 2007 Honda Pilot, and 2006 Honda Pilot. However, it is still accessible from the selected car via links, so may be relevant.
  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 Multiplex Control Unit Connector Terminals
      G04247210Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. With the driver's multiplex control unit still disconnected, make these input tests at the connector or driver's under-dash 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.
      REFERENCE CHART (DRIVER'S MULTIPLEX CONTROL UNIT DISCONNECTED)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      A1 Fuse/relay box socket Under all conditions Attach to ground:
      The ignition key light should come on.
      • Blown No. 47 (20 A) fuse in the under-hood fuse/relay box
      • Blown LED
      • An open in the wire
      A24 Ignition switch ON (II) Check for voltage to ground:
      There should be battery voltage.
      • Blown No. 9 (10 A) fuse in the driver's under-dash fuse/relay box
      • Faulty driver's under-dash fuse/relay box
      A6 Fuse/relay box socket Combination light switch ON Check for voltage to ground:
      There should be battery voltage and jump 12V to driver's multiplex connector B16 (EX).
      • Blown No. 54 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 10 (15 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty taillight relay
      • Faulty combination light switch
      • An open in the wire
  5. Reconnect the driver's multiplex control unit to the driver's under-dash fuse/relay box, and perform the following input tests at the appropriate connectors on the back of the driver's under-dash fuse/relay box. For driver's under-dash fuse/relay box connector socket location (see DRIVER'S UNDER-DASH 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.
      REFERENCE CHART (DRIVER'S MULTIPLEX CONTROL UNIT CONNECTED)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      E3 GRN/ORN 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.
      • A short to ground
      • Faulty driver's door switch
      • An open in the wire
      M9 BLU/BLK Ignition key is in the ignition switch Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G401)
      • Faulty ignition switch
      • An open in the wire
      Ignition key is out of the ignition switch Check for voltage to ground: There should be 5 V or more.
      • A short to ground
      • Poor ground (G401)
      • Faulty ignition switch
      • An open in the wire
      E10 LT GRN/BLK 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.
      • A short to ground
      • Faulty left rear door switch
      • An open in the wire
      B81 (1) ORN Tailgate open Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G652)
      • Faulty tailgate latch switch
      • An open in the wire
      Tailgate closed Check for voltage to ground:
      There should be 5 V or more.
      • Short to ground
      • Poor ground (G652)
      • Faulty tailgate latch switch
      • An open in the wire
      (1) Driver's multiplex control unit connector B

      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 2: Identifying Passenger's Under-Dash Fuse/Relay Box Socket (Passenger's Multiplex Control Unit Connector Terminals)
      G04247211Courtesy of AMERICAN HONDA MOTOR CO., INC.
  8. With the passenger's multiplex control unit still disconnected, make these input tests at the connector and passenger's under-dash 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.
      REFERENCE CHART

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      A22 Fuse/relay box socket Ignition switch ON (II) Check for voltage to ground: There should be battery voltage.
      • Blown No. 9 (10 A) fuse in the driver's under-dash fuse/relay box
      • Faulty passenger's under-dash fuse/relay box
      • An open in the wire
      A21 Interior light switches in the middle (Door) position Attach to ground:
      Interior lights should come on.
      • Blown No. 11 (10 A) fuse in the passenger's under-dash fuse/relay box
      • Blown No. 54 (40 A) fuse in the under-hood fuse/relay box
      • Faulty passenger's under-dash fuse/relay box
      • Faulty individual map light
      • Faulty interior lights switch
      • An open in the wire
  9. Reconnect the passenger's multiplex control unit to the passenger's under-dash fuse/relay box, and perform the following input tests at the appropriate connector of the passenger's under-dash 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.
      REFERENCE CHART (PASSENGER'S MULTIPLEX CONTROL UNIT TO PASSENGER'S UNDER-DASH FUSE/RELAY BOX CONNECTED)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      C16 WHT/ORN 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
      • A short to ground in the wire
      C14 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
      • A short to ground in the wire

      Door Multiplex Control Unit 

  10. Remove the driver's door panel and disconnect the 20P connector from the door multiplex control unit.
  11. 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 12.
      Fig 3: Identifying Door Multiplex Control Unit Connector A Terminals
      G04247212Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. Reconnect the connector to the door multiplex control 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.
      REFERENCE CHART (DOOR MULTIPLEX CONTROL UNIT CONNECTOR A)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      A17 BLK/RED Driver's door lock knob unlocked Check for voltage to ground: There should be less than 1 V.
      • Faulty driver's door lock actuator
      • Poor ground (G401)
      • An open in the wire
      Driver's door lock knob locked Check for voltage to ground: There should be 5 V or more.
      • Faulty driver's door lock actuator
      • Short to ground
  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 most likely unit to be at fault, and recheck. If the system works properly, the original unit is faulty; replace it.
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