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Home >> Acura >> 2003 >> MDX Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Keyless/Power Door Locks/Security System >> Control Unit Input Test >> Passenger's Unit
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Passenger's Unit

  1. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box, and disconnect its connector.
  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: Passenger's Under-Dash Fuse/Relay Box Socket
      G03642361Courtesy of AMERICAN HONDA MOTOR CO., INC.
      Fig 2: Passenger's Multiplex Control Unit Connector B
      G03642362Courtesy of AMERICAN HONDA MOTOR CO., INC.
      Fig 3: Passenger's Under-Dash Fuse/Relay Box Connector C
      G03642363Courtesy of AMERICAN HONDA MOTOR CO., INC.
      Fig 4: Passenger's Under-Dash Fuse/Relay Box Connector E
      G03642364Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. With the passenger's multiplex control unit still disconnected, make these input tests at the connectors and the passenger's under-dash fuse/relay box sockets.
    • 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.
      CONTROL UNIT INPUT TEST (PASSENGER'S UNIT - 1 OF 2)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      B22(1) BLK Under all conditions Check for continuity to ground:
      There should be continuity.
      • Poor ground (G503)
      • Faulty passenger's fuse/relay box
      • An open in the wire
      A8 Fuse/relay box socket Under all conditions Check for continuity to ground:
      There should be continuity.
      • Poor ground (G651)
      • Faulty passenger's fuse/relay box
      • An open in the wire
      A9 Under all conditions Attach to ground:
      Horns should sound.
      • Blown No. 47 (20 A) fuse in the under-hood fuse/relay box
      • Faulty passenger's fuse/relay box
      • Faulty horn relay
      • Faulty horn
      • An open in the wire
      A20 Under all conditions Attach to ground:
      Headlights should come on.
      • Faulty headlight relay 1 or 2
      • Faulty passenger's fuse/relay box
      • 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
      • Faulty driver's fuse/relay box
      • Faulty passenger's fuse/relay box
      • An open in the wire
      A23 Under all conditions Check for voltage to ground:
      There should be battery voltage.
      • Blown No. 12 (20 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty passenger's fuse/relay box
      A24 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
      • Faulty passenger's fuse/relay box
      A10 Fuse/relay box socket Jump A10 to battery voltage and B11 to body ground. Check driver's door lock operation:
      The door should lock.
      • Faulty driver's door lock actuator
      • Faulty passenger's fuse/relay box
      • An open in the wire
      B11(1) YEL
      A10 Fuse/relay box socket Jump A10 to battery voltage and A11 to body ground. Check passenger's doors lock operation:
      The door should lock.
      • Faulty passenger's door lock actuator
      • Faulty passenger's fuse/relay box
      • An open in the wire
      A11 Check tailgate lock operation:
      The tailgate should lock.
      • Faulty tailgate lock actuator
      • Faulty passenger's fuse/relay box
      • An open in the wire
      A1 PNK Connect A1 terminal to A24 terminal momentarily. Check keyless buzzer operation:
      The buzzer should sound.
      • Poor ground (G652(2) or G503(3) )
      • Faulty keyless buzzer
      • Faulty passenger's fuse/relay box
      • An open in the wire
      B21(1) BLU Under all conditions Check for continuity to ground:
      There should be continuity.
      • Poor ground (G502)
      • Faulty connections at the audio unit or navigation display unit
      • Faulty audio unit or navigation display unit
      • Faulty passenger's fuse/relay box
      • An open in the wire
      (1) Passenger's Multiplex Control Unit Connector B
      (2) '03 Model
      (3) '04-'06 Models
  4. Reconnect the passenger's multiplex control unit to the passenger's under-dash fuse/relay box, turn the ignition switch ON (II) to keep the system awake, and perform the following input tests at the appropriate connectors on the passenger's under-dash fuse/relay box. For passenger's under-dash fuse/relay box connector socket location (see PASSENGER'S UNDER-DASH FUSE/RELAY BOX ).
    NOTE: When testing passenger's door lock knob switches, begin with all doors locked, then test one at a time.
    • 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 1 in DOOR UNIT  .
      CONTROL UNIT INPUT TEST (PASSENGER'S UNIT - 2 OF 2)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      C16 GRN Passenger's door open Check for voltage to ground:
      There should be less than 1 V.
      • Faulty passenger's door switch
      • An open in the wire
      • Short to ground
      Passenger's door closed Check for voltage to ground:
      There should be 5 V or more.
      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
      • Short to ground
      Right rear door closed Check for voltage to ground:
      There should be 5 V or more.
      C8 RED/BLU Wake up the multiplex system by locking all doors with the power door lock switch; Left rear door lock knob switch unlocked Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G601)
      • Faulty left rear door lock actuator
      • An open in the wire
      • Short to ground
      Wake up the multiplex system by locking all doors with the power door lock switch; Left rear door lock knob switch locked Check for voltage to ground:
      There should be 5 V or more.
      Wake up the multiplex system by locking all doors with the power door lock switch; Right rear door lock knob switch unlocked Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G652)
      • Faulty right rear door lock actuator
      • An open in the wire
      • Short to ground
      Wake up the multiplex system by locking all doors with the power door lock switch; Right rear door lock knob switch locked Check for voltage to ground:
      There should be 5 V or more.
      E2 GRN/BLK Wake up the multiplex system by locking all doors with the power door lock switch; Passenger's door lock knob switch unlocked Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G651)
      • Faulty passenger's door lock actuator
      • An open in the wire
      • Short to ground
      Wake up the multiplex system by locking all doors with the power door lock switch; Passenger's door lock knob switch locked Check for voltage to ground:
      There should be 5 V or more.
      E5 BLU/ORN Passenger's door lock switch in UNLOCK Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G651)
      • Faulty passenger's door lock switch
      • An open in the wire
      • Short to ground
      Passenger's door lock switch in neutral position Check for voltage to ground:
      There should be 5 V or more.
      E6 BLK/ORN Passenger's door lock switch in LOCK Check for voltage to ground:
      There should be less than 1 V.
      Passenger's door lock switch in neutral position Check for voltage to ground:
      There should be 5 V or more.
      B21(1) BLU Under all conditions Check for voltage to ground:
      There should be less than 1 V.
      • Poor ground (G502)
      • Poor connection at audio unit or navigation display unit
      • Faulty audio unit or navigation display unit.
      • An open in the wire
      (1) Passenger's Multiplex Control Unit Connector B
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