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Control Unit Input Test

NOTE: These tests cover the door, driver's, and passenger's multiplex control units.
  1. Before testing the power door lock and security control functions, troubleshoot the multiplex control system (see TROUBLESHOOTING ).

    Driver's 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.

      DRIVER'S UNDER-DASH FUSE/RELAY BOX SOCKET 

      (Driver's multiplex control unit connector A)

      Fig 1: Identifying Driver's Multiplex Control Unit Connector Terminals
      G04548438Courtesy of AMERICAN HONDA MOTOR CO., INC.

      DRIVER'S MULTIPLEX UNIT CONNECTOR B 

      Fig 2: Identifying Driver's Multiplex Unit Connector Terminals
      G04548439Courtesy of AMERICAN HONDA MOTOR CO., INC.

      DRIVER'S UNDER-DASH FUSE/RELAY BOX CONNECTOR E 

      Fig 3: Identifying Driver's Under-Dash Fuse/Relay Box Connector Terminals
      G04548440Courtesy of AMERICAN HONDA MOTOR CO., INC.

      DRIVER'S UNDER-DASH FUSE/RELAY BOX CONNECTOR M 

      Fig 4: Identifying Driver's Under-Dash Fuse/Relay Box Connector Terminals
      G04548441Courtesy of AMERICAN HONDA MOTOR CO., INC.

      *: EX and EXL 

  4. With the driver's multiplex control unit still disconnected, make these input tests at the connector and driver'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 5.
      RESULT REFERENCE CHART (DRIVER'S MULTIPLEX CONTROL UNIT CONNECTOR DISCONNECTED AND DRIVER'S UNDER-DASH FUSE/RELAY BOX SOCKETS)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      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
      • Faulty driver's fuse/relay box
      • 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 fuse/relay box
      A(1) Under all conditions Attach to ground: The security indicator should come on.
      • Blown No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty security indicator
      • Faulty driver's fuse/relay box
      • An open in the wire
      A22 (2) Connect B16 to battery voltage and A22 to ground The parking lights and dash lights should come on.
      • Blown No. 10 (15 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty taillight relay
      • Faulty driver's fuse/relay box
      • An open in the wire
      B16(1)(2) RED/GRN Combination light switch OFF Check for continuity to ground: There should be no continuity.
      • Faulty taillight relay
      • Faulty combination light switch
      • Faulty driver's fuse/relay box
      • An open in the wire
      • A short to ground in the wire
      Combination light switch ON and jump B16 to battery voltage The parking lights and dash lights should come on.
      • Blown No. 10 (15 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty taillight relay
      • Faulty combination light switch
      • Faulty driver's fuse/relay box
      • An open in the wire
      (1) Driver's multiplex control unit connector B
      (2) EX and EXL
  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 CONNECTOR TO FUSE/RELAY BOX INDEX ).

    • 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.
      RESULT REFERENCE CHART (DRIVER'S MULTIPLEX CONTROL UNIT CONNECTED TO DRIVER'S UNDER-DASH FUSE/RELAY BOX)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      B2(1)(2) GRN/BLK Wake up the multiplex system by locking all doors and tailgate with the power door lock switch; Left rear door lock knob switch unlocked Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G601)
      • Faulty left rear door lock knob switch
      • An open in the wire
      Wake up the multiplex system by locking all doors and tailgate 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.
      • Faulty left rear door lock knob switch
      • A short to ground in the wire
      B6 (1)(2) YEL Hood open Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G201)
      • Faulty hood switch
      • An open in the wire
      Hood closed Check for voltage to ground: There should be 5 V or more.
      • Faulty hood switch
      • A short to ground in the wire
      B8 (1) ORN Tailgate open Check for voltage to ground: There should be 1 V or less.
      • 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.
      • Faulty tailgate latch switch
      • A short to ground in the wire
      E3 GRN/ORN Driver's door open Check for voltage to ground: There should be 1 V or less.
      • 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
      • A short to ground in the wire
      E10 LT GRN/BLK Left rear door open Check for voltage to ground: There should be 1 V or less.
      • 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
      • A short to ground in the wire
      M9 BLU/BLK Ignition key is in the ignition switch Check for voltage to ground: There should be 5 V or more.
      • Poor ground (G401)
      • Faulty ignition key switch
      • An open in the wire
      Ignition key is out of the ignition switch Check for voltage to ground: There should be less than 1 V.
      • Faulty ignition key switch
      • A short to ground in the wire
      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
      (1) Driver's multiplex control unit connector B
      (2) EX and EXL

      Passenger's 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.

      PASSENGER'S UNDER-DASH FUSE/RELAY BOX SOCKET 

      Fig 5: Identifying Passenger's Under-Dash Fuse/Relay Box Socket Terminals
      G04548442Courtesy of AMERICAN HONDA MOTOR CO., INC.

      PASSENGER'S MULTIPLEX CONTROL UNIT CONNECTOR B 

      Fig 6: Identifying Passenger's Multiplex Control Unit Connector Terminals
      G04548443Courtesy of AMERICAN HONDA MOTOR CO., INC.

      PASSENGER'S UNDER-DASH FUSE/RELAY BOX CONNECTOR C 

      Fig 7: Identifying Passenger's Under-Dash Fuse/Relay Box Connector Terminals
      G04548444Courtesy of AMERICAN HONDA MOTOR CO., INC.

      PASSENGER'S UNDER-DASH FUSE/RELAY BOX CONNECTOR E 

      Fig 8: Identifying Passenger's Under-Dash Fuse/Relay Box Connector Terminals
      G04548445Courtesy of AMERICAN HONDA MOTOR CO., INC.

      *: EX and EXL 

  8. 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 9.
      RESULT REFERENCE CHART (PASSENGER'S MULTIPLEX CONTROL UNIT DISCONNECTED, MAKE INPUT TESTS AT CONNECTORS AND PASSENGER'S UNDER-DASH FUSE/RELAY BOX SOCKETS)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      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(2) 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 doors 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
      B21 (1) BLU Under all conditions Check for continuity to ground: There should be continuity.
      • Poor ground (G504)
      • Faulty connections at the audio unit, DVD player, rear controller and screen, navigation display unit
      • Faulty audio unit, DVD player, rear controller and screen, navigation display unit
      • Faulty passenger's fuse/relay box
      • An open in the wire
      (1) Passenger's multiplex control unit connector B
      (2) EX and EXL
  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 connectors on the passenger's under-dash fuse/relay box.

    For passenger's under-dash fuse/relay box connector socket location (see CONNECTOR TO FUSE/RELAY BOX INDEX ).

    • 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.
      RESULT REFERENCE CHART (PERFORM FOLLOWING INPUT TESTS AT APPROPRIATE CONNECTORS ON PASSENGER'S UNDER-DASH FUSE/RELAY BOX)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      C8 (2) RED/BLU
      NOTE: Front passenger's door lock knob switch in the locked position
      		 Wake up the multiplex system by locking all doors and tailgate with the power door lock switch; Right rear door lock knob switch unlocked Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G651)
      • Faulty right rear door lock actuator
      • An open in the wire
      Wake up the multiplex system by locking all doors and tailgate 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.
      • Faulty right rear door lock actuator
      • A short to ground in the wire
      E2 () GRN/RED
      NOTE: Right rear door lock knob switch in the locked position
      		 Wake up the multiplex system by locking all doors and tailgate with the power door lock switch; Front passenger's door lock knob switch unlocked Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G651)
      • Faulty front passenger's door lock actuator
      • An open in the wire
      Wake up the multiplex system by locking all doors and tailgate with the power door lock switch; Front passenger's door lock knob switch locked Check for voltage to ground: There should be 5 V or more.
      • Faulty front passenger's door lock actuator
      • A short to ground in the wire
      B21 (1) BLU Under all conditions Check for voltage to ground: There should be battery voltage.
      • Poor ground (G504)
      • Poor connection at audio unit, DVD player, rear controller and screen, navigation display unit
      • Faulty audio unit, DVD player, rear controller and screen, navigation display unit
      • An open in the wire
      B22 (1) BLK Under all conditions Check for voltage to ground: There should be less than 1 V.
      • Poor ground (G503)
      • Faulty passenger's fuse/relay box
      • An open in the wire
      (1) Passenger's multiplex control unit connector B
      (2) EX and EXL
      RESULT REFERENCE CHART (PERFORM FOLLOWING INPUT TESTS AT APPROPRIATE CONNECTORS ON PASSENGER'S UNDER-DASH FUSE/RELAY BOX)

      Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
      C14 GRN/WHT Right rear door open Check for voltage to ground: There should be 1 V or less.
      • 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
      C16 GRN Front passenger's door open Check for voltage to ground: There should be 1 V or less.
      • 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
      E5 BLU/ORN Front passenger's door lock switch in UNLOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G652)
      • Faulty front passenger's door lock switch
      • An open in the wire
      Front passenger's door lock switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty front passenger's door lock switch
      • A short to ground in the wire
      E6 BLK/ORN Front passenger's door lock switch in LOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G651)
      • Faulty front passenger's door lock switch
      • An open in the wire
      Front passenger's door lock switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty front passenger's door lock switch
      • A short to ground in the wire
      E7 BLK/RED Front passenger's door key cylinder switch in UNLOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G651)
      • Faulty or misadjusted front passenger's door key cylinder switch
      • An open in the wire
      Front passenger's door key cylinder switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty or misadjusted front passenger's door key cylinder switch
      • An open in the wire
      E3 BLU/GRN Front passenger's door key cylinder switch in LOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G651)
      • Faulty or misadjusted front passenger's door key cylinder switch
      • An open in the wire
      Front passenger's door key cylinder switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty or misadjusted front passenger's door key cylinder switch
      • A short to ground in the wire
      B8(1) RED/BLK Tailgate key cylinder switch in UNLOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G652)
      • Faulty or misadjusted tailgate key cylinder switch
      • An open in the wire
      Tailgate key cylinder switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty or misadjusted tailgate key cylinder switch
      • A short to ground in the wire
      B7(1) RED/WHT Tailgate key cylinder switch in LOCK Check for voltage to ground: There should be 1 V or less.
      • Poor ground (G652)
      • Faulty or misadjusted tailgate key cylinder switch
      • An open in the wire
      Tailgate key cylinder switch in neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty or misadjusted tailgate key cylinder switch
      • A short to ground in the wire
      (1) Passenger's multiplex control unit connector B

      Door Unit 

  10. Remove the door multiplex control unit, and disconnect its connector.
  11. Inspect the 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 9: Identifying Connector Terminals
      G04548446Courtesy of AMERICAN HONDA MOTOR CO., INC.

      *: EX and EXL 

  12. Reconnect the connector to the control unit, and make these input tests at the connector.
    • 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 13.
      RESULT REFERENCE CHART (DOOR MULTIPLEX CONTROL UNIT, DISCONNECTED)

      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
      • An open in the wire
      A12 BLK Under all conditions Check for voltage to ground: There should be less than 1 V.
      • Poor ground (G401)
      • An open in the wire
      A6(1) BLU/WHT 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 (G401)
      • An open in the wire
      • Short to ground in the wire
      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.
      A16 BLU 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 (G401)
      • An open in the wire
      • Short to ground in the wire
      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.
      A7 PNK Driver's door lock knob locked 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 unlocked Check for voltage to ground: There should be 5 V or more.
      • Faulty driver's door lock actuator
      • Short to ground in the wire
      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 in the wire
      A8 BLK/WHT Driver's door lock switch in LOCK Check for voltage to ground: There should be less than 1 V.
      • Faulty driver's door lock switch
      • Poor ground (G401)
      • An open in the wire
      Driver's door lock switch in the neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty driver's door lock switch
      • Short to ground in the wire
      A18 GRN/RED Driver's door lock switch in UNLOCK Check for voltage to ground: There should be less than 1 V.
      • Faulty driver's door lock switch
      • Poor ground (G401)
      • An open in the wire
      Driver's door lock switch in the neutral position Check for voltage to ground: There should be 5 V or more.
      • Faulty driver's door lock switch
      • Short to ground in the wire
      (1) EX and EXL
  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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