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Passenger's Unit

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. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box.
  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.
      Fig 1: Removing Passenger's Multiplex Control Unit From Passenger's Under-Dash Fuse/Relay Box
      G04247319Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Make the following input tests at the 22P connector B and the passenger's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
    • 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.
      TERMINALS REFERENCE CHART (22P CONNECTOR B AND PASSENGER'S UNDER-DASH FUSE/RELAY BOX SOCKET CONNECTOR A)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      B22 (1) BLK Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G503)
      • An open in the wire
      A24 Fuse/relay box socket Under all conditions Check for voltage to ground:
      There should be battery voltage.
      • Blown No. 13 (7.5 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
      A8 Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G651)
      • An open in the wire
      A22 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
      • An open in the wire
      A12 Under all conditions Attach A12 to battery voltage:
      Power window relay should click and check voltage between No. 7 (20 A) fuse and ground:
      There should be battery voltage.
      • Poor ground (G651)
      • Faulty passenger's fuse box
      • Faulty power window relay
      • An open in the wire
      • Blown No. 51 (40 A) fuse in the under-hood fuse/relay box
      (1) Make this test with all connectors reconnected

    4. Door Unit 

  4. Carefully pry off the driver's door switch trim (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  5. Disconnect the connectors (A).
    Fig 2: Disconnecting Connectors And Identifying Connector Terminals
    G04247320Courtesy of AMERICAN HONDA MOTOR CO., INC.
  6. 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 7.
  7. Make the following input tests at connector A (20P).
    • 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 8.
      TERMINALS REFERENCE CHART (CONNECTOR A (20P))

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      A1 WHT/RED Under all conditions Check for voltage to ground:
      There should be battery voltage.
      • Blown No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box
      • Blown No. 54 (40 A) fuse in the under-hood fuse/relay box
      • An open in the wire
      A2 WHT/YEL Ignition switch ON (II) and passenger's multiplex terminal A12 connected to battery voltage Check for voltage to ground on A2:
      There should be battery voltage.
      • Blown No. 51 (40 A) fuse in the under-hood fuse/relay box
      • Blown No. 7 (20 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty power window relay
      • An open in the wire
      A12(1) Fuse/relay box socket
      A12(2) BLK Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G401)
      • An open in the wire
      A13 (2) BLK Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G601)
      • An open in the wire
      (1) Passenger's multiplex control unit connector A
      (2) Make this test with all connectors reconnected

    8. Driver's Unit 

  8. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
  9. 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 10.
      Fig 3: Removing Driver's Multiplex Control Unit From Driver's Under-Dash Fuse/Relay Box And Identifying Connector Terminals
      G04247321Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Make the following input tests at 22P connector B and the driver's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, one of the multiplex control units (door, driver's or passenger's) must be faulty. Substitute a known-good control unit for the one that's is most closely related to the failure, then recheck. If the symptom continues, replace the next most likely control unit until the symptom goes away.
      TERMINALS REFERENCE CHART (22P CONNECTOR B AND DRIVER'S UNDER-DASH FUSE/RELAY BOX SOCKET CONNECTOR A)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      B11(1) BLK Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G501)
      • An open in the wire
      A12 Fuse/relay box socket Under all conditions Check for voltage to ground:
      There should be battery voltage.
      • Blown No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box
      • Blown No. 54 (40 A) fuse in the under-hood fuse/relay box
      • An open in the wire
      A14 Under all conditions Check for continuity to ground:
      There should be continuity.
      • Poor ground (G401)
      • 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
      • An open in the wire
      A13 Ignition key is inserted into the ignition switch Check for continuity to ground:
      There should be continuity.
      • Faulty ignition key switch
      • An open in the wire
      • Poor ground (G401)
      Ignition key removed from the ignition switch Check for continuity to ground:
      There should be no continuity.
      • Faulty ignition key switch
      • Short to ground
      A1 Under all conditions Attach to ground: 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
      A15 Short the multiplex control inspection connector terminals with the special tool Check for continuity to ground:
      There should be continuity.
      • Poor ground (G401)
      • Faulty driver's fuse/relay box
      • An open in the wire
      Remove the special tool from the multiplex control inspection connector Check for continuity to ground:
      There should be no continuity.      		 Short to ground
      (1) Make this test with all connectors reconnected
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