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Control Unit Input Test

NOTE: Before troubleshooting the keyless entry/security control system, troubleshoot the multiplex integrated control system first using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

MICU 

  1. Turn the ignition switch to LOCK (0).
  2. Remove the left front door sill trim and left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Disconnect the under-dash fuse/relay box connectors E, F, H, J, K, N, P and Q.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors Terminals
    G05968663Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. 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 5.
  5. With the connectors still disconnected, do the following input tests:
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If the input tests prove OK, Go to step  6.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    K2 YEL/GRN Connect the battery positive terminal to terminal K12(K2), and terminal K2 (K12) to terminal H9 Check actuator operation: The driver's door lock actuator should lock (unlock).
    • Faulty driver's door lock actuator
    • An open or high resistance n the wire
    K12 YEL/BLK
    N7 YEL/BLK Connect the battery positive terminal to terminal N7 (N9), and terminal N9 (N7) to terminal H9 Check actuator operation: The front passenger's door lock actuator should lock (unlock).
    • Faulty front passenger's door lock actuator
    • An open or high resistance in the wire
    N9 YEL
    H3 YEL/BLK Connect the battery positive terminal to terminal H3(H10), and terminal H10 (H3) to terminal H9 Check actuator operation: The left rear door lock actuator should lock (unlock).
    • Faulty left rear door lock actuator
    • An open or high resistance in the wire
    H10 YEL
    E2 YEL/BLK Connect the battery positive terminal to terminal E2 (E8), and terminal E8 (E2) to terminal H9 Check actuator operation: The right rear door lock actuator should lock (unlock).
    • Faulty right rear door lock actuator
    • An open or high resistance in the wire
    E8 YEL
    F5 RED/WHT Connect the battery positive terminal to terminal F5 with the trunk lid main switch ON Check actuator operation: The in-bed trunk lid actuator should unlock.
    • Poor ground (G601) or an open in the ground wire
    • Faulty in-bed trunk lid main switch
    • Faulty in-bed trunk lid actuator
    • An open or high resistance in the wire
  6. Reconnect all connectors to the under-dash fuse/relay box. Turn the ignition switch to ON (II), and do the following input tests:
    • 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 7.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    P1 BLK In all ignition switch positions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G403)
    • An open or high resistance in the wire
    H9 BLK In all ignition switch positions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G501)
    • An open or high resistance in the wire
    P29(1) BRN/WHT Front passenger's door lock knob switch unlocked Measure the voltage to ground:
    There should be less than 0.2V.
    • Poor ground (G402)
    • Faulty front passenger's door lock knob switch
    • An open or high resistance in the wire
    Front passenger's door lock knob switch locked Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty front passenger's door lock knob switch
    • A short to ground in the wire
    P9 PNK/BLU Front passenger's door lock switch unlocked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G402) or an open in the ground wire
    • Faulty front passenger's door lock switch
    • An open or high resistance in the wire
    Front passenger's door lock switch in neutral Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty front passenger's door lock switch
    • A short to ground in the wire
    P25 PNK/BLK Front passenger's door lock switch locked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G402) or an open in the ground wire
    • Faulty front passenger's door lock switch
    • An open or high resistance in the wire
    Front passenger's door lock switch in neutral Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty front passenger's door lock switch
    • A short to ground in the wire
    Q2(1) BLK/WHT Left rear door lock knob switch unlocked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G501) or an open in he ground wire
    • Faulty left rear door lock knob switch
    • An open or high resistance in the wire
    Left rear door lock knob switch locked Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty left rear door lock knob switch
    • A short to ground in the wire
    Q3(1) BLK/RED Right rear door lock knob switch unlocked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G501) or an open in the ground wire
    • Faulty right rear door lock knob switch
    • An open or high resistance in the wire
      Right rear door lock knob switch locked Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty right rear door lock knob switch
    • A short to ground in the wire
    Q12 RED/BLU In-bed trunk lid handle switch ON Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G602) or an open in the ground wire
    • Faulty in-bed trunk lid handle switch
    • An open or high resistance in the wire
    In-bed trunk lid handle switch OFF Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty in-bed trunk lid handle switch
    • A short to ground in the wire
    Q4(2) GRY/BLU In-bed trunk lid key cylinder switch unlocked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G602) or an open in the ground wire
    • Faulty In-bed trunk lid key cylinder switch
    • An open or high resistance in the wire
    In-bed trunk lid key cylinder switch in neutral Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty In-bed trunk lid key cylinder switch
    • A short to ground in the wire
    P27(1) RED/WHT Under all conditions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G404) or an open in the ground wire
    • Faulty connections at the audio unit
    • Faulty CD changer (with navigation system)
    • Faulty audio unit (without navigation system)
    • An open or high resistance in the wire
    P13 RED/WHT Ignition key inserted into the ignition switch Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G401) or an open in the ground wire
    • Faulty ignition key switch
    • An open or high resistance in the wire
    Ignition switch in LOCK (0) and ignition key removed from the ignition switch Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty ignition key switch
    • A short to ground in the wire
    E15 GRN Driver's door open Measure the voltage to ground:
    There should be less than 1 V.
    • Faulty driver's door switch
    • An open in the wire
    Driver's door closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty driver's door switch
    • A short to ground in the wire
    H12 LT GRN/RED Front passenger's door open Measure the 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 Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty front passenger's door switch
    • A short to ground in the wire
    E14 GRN/YEL Left rear door open Measure the voltage to ground:
    There should be less than 1 V.
    • Faulty left rear door switch
    • An open in the wire
    Left rear door closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty left rear door switch
    • A short to ground in the wire
    H13 GRN/WHT Right rear door open Measure the voltage to ground:
    There should be less than 1 V.
    • Faulty right rear door switch
    • An open in the wire
    Right rear door closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty right rear door switch
    • A short to ground in the wire
    Q7 BLU/YEL In-bed trunk lid open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G601)
    • Faulty In-bed trunk lid latch switch
    • An open in the wire
    In-bed trunk lid closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty In-bed trunk lid latch switch
    • A short to ground in the wire
    Q11 BLU/ORN Tailgate open Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G602)
    • Faulty tailgate switch
    • An open in the wire
    Tailgate closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty tailgate switch
    • A short to ground in the wire
    (1) RTS, RTL, and EX-L models
    (2) After testing, insert the key into the ignition switch and turn the ignition switch to ON (II) before continuing to the next step.
    (3) If the factory-installed audio unit or audio disc changer is removed from the vehicle, this voltage will be between 10-12V.

    Relay Control Module 

  7. Turn the ignition switch to LOCK (0).
  8. Remove the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).
  9. Remove the under cover from the under-hood fuse/relay box, and disconnect connector H (18P).
    Fig 2: Identifying Under-Hood Fuse/Relay Box Connector H (18P) Terminals
    G05968664Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. 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 11.
  11. With the connector still disconnected, do these input tests at the following 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 12.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    H1
    .
    H9    		 BLU/RED Under all conditions Connect the battery power to terminal H1 (H9) momentarily: There horn should sound.
    • Faulty horn
    • An open in the wire
  12. Reconnect the connector to the under-hood fuse/relay box, turn the ignition switch to ON (II) and do the following input tests:
    • 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.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    H2 GRN/BLK Hood open Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G201) or an open in the ground wire
    • Faulty hood switch
    • An open or high resistance in the wire
    Hood closed Measure the voltage to ground:
    There should be more than 5 V.
    • Faulty hood switch
    • A short to ground in the wire

    Door Multiplex Control Unit 

  13. Turn the ignition switch to LOCK (0).
  14. Remove the power window master switch (see PASSENGER'S POWER WINDOW MOTOR TEST ).
  15. Disconnect the 23P connector from the power window master switch.
    Fig 3: Identifying Door Multiplex Control Unit 23P Connector Terminals
    G05968665Courtesy of AMERICAN HONDA MOTOR CO., INC.
  16. 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 17.
  17. With the connector still disconnected, do these input tests at the following connector.
    • If the test indicates a problem, find and correct the cause, then recheck the system.
    • If the input test proves OK, Go to step 18.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    16 BRN/BLK Under all conditions Check for continuity between terminal No. 16 and under-dash fuse/relay box connector J (21P) terminal No. 4:
    There should be continuity.    		 An open or high resistance in the wire
    Check for continuity between terminal No. 16 and body ground:
    There should be no continuity.    		 A short to ground in the wire
  18. Reconnect the connector to the door multiplex control unit. Turn the ignition switch to ON (II) and do the following input tests:
    • 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 19.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    1 BLK In all ignition switch conditions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G501)
    • An open or high resistance in the wire
    15 WHT/RED Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 7 (7.5 A) fuse in the under-dash fuse/relay box.
    • An open or high resistance in the wire
    20 YEL Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 21 (7.5 A) fuse in the under-dash fuse/relay box.
    • An open or high resistance in the wire
    7 WHT/BLK Driver's door lock knob switch unlocked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G401) or an open in the ground wire
    • Faulty driver's door lock knob switch
    • An open or high resistance in the wire
    Driver's door lock knob switch locked Measure the voltage to ground:
    There should be more than 0.2 V.
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    22 YEL/RED Driver's door lock knob switch locked Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G401) or an open in the ground wire
    • Faulty driver's door lock knob switch
    • An open or high resistance in the wire
    Driver's door lock knob switch unlocked Measure the voltage to ground:
    There should be at least 5 V.
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    8 WHT/RED Driver's door key cylinder switch in LOCK Measure the voltage to ground:
    There should be less than 0.2 V.
    • Faulty driver's door key cylinder switch
    • Poor ground (G401) or an open in the ground wire
    • An open or high resistance in the wire
    Driver's door key cylinder switch in neutral Measure the voltage to ground:
    There should be atleast 5 V.
    • A short to ground in the wire
    • Faulty driver's door key cylinder switch
    Driver's door key cylinder switch in UNLOCK Measure the voltage to ground:
    There should be at least 5 V.
    21 WHT Driver's door key cylinder switch in UNLOCK Measure the voltage to ground:
    There should be less than 0.2 V.
    • Faulty driver's door key cylinder switch
    • Poor ground (G401) or an open in the ground wire
    • An open or high resistance in the wire
    Driver's door key cylinder switch in neutral Measure the voltage to ground:
    There should be at least 5 V.
    • A short to ground in the wire
    • Faulty driver's door key cylinder switch
    Driver's door key cylinder switch in LOCK Measure the voltage to ground:
    There should be at least 5 V.
  19. If all the input tests prove OK, and no DTCs were found during multiplex integrated control system troubleshooting (B-CAN System Diagnostic Test Mode A) (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ), go to the B-CAN system input and output index (see B-CAN SYSTEM UNIT INPUT/OUTPUT DEVICE CONTROLLED ). If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU). If input failures are related to a particular control unit, replace that control unit.
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