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Home >> Acura >> 2009 >> TSX Standard >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Keyless/Power Door Locks/Security System (4-CYL) >> Control Unit Input Test
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Control Unit Input Test

NOTE: Before testing, troubleshoot the multiplex integrated control system first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ), and make sure the lighting system works properly

Driver's MICU 

  1. Turn the ignition switch to LOCK (0)
  2. Remove the driver's dashboard undercover (see DRIVER'S POCKET REMOVAL/INSTALLATION ), then remove the dashboard lower cover (see DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION )
  3. Disconnect driver's under-dash fuse/relay box connectors D, F, G, N, Q, and R
    NOTE: All connector views are wire side of female terminals
    Fig 1: Identifying Driver's Under-Dash Fuse/Relay Box Connectors D, F, G, N, Q And R
    G05994894Courtesy 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 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 6
    NOTE: Before testing, make sure the No 15(10 A) fuse in the under-hood fuse/relay box is OK
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    D2 YEL Connect terminal F11 to terminal D2 (or D9), and terminal D9 (or D2) to body ground Check actuator operation The left rear door lock actuator should UNLOCK (or LOCK)
    • Faulty left rear door lock actuator
    • An open in the wire
    D9 ORN
    D16 ORN Connect terminal F11 to terminal D16 momentarily Check actuator operation The trunk lid release actuator should work
    • Poor ground(G901)
    • Faulty trunk lid release actuator
    • An open in the wire
    F23 GRY Under all conditions Attach to ground The horns should sound
    • Blown No 10(10A) fuse in the under-hood fuse/relay box
    • Faulty horn relay
    • Faulty horn
    • An open in the wire
    N1 YEL Connect terminal F11 to terminal N1 (or N2), and terminal N2 (or N1) to body ground Check actuator operation The driver's door lock actuator should UNLOCK (or LOCK)
    • Faulty driver's door lock actuator
    • An open in the wire
    N2 ORN
    N1 YEL Connect terminal F11 to terminal N1 (or D9), and terminal D9 (or N1) to body ground Check actuator operation The fuel fill door lock actuator should UNLOCK (or LOCK)
    • Faulty fuel fill door lock actuator
    • An open in the wire
    D9 ORN
  6. Reconnect the connectors to the driver's under-dash fuse/relay box, and 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 7
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test-Desired result Possible cause if desired result is not obtained
    D8 BLK Under all conditions Measure the voltage to ground There should be less than 0 5 V.
    • Poor ground (G601)
    • An open in the wire
    Q1 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground (G502)
    • An open in the wire
    Q2 BRN Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G501)
    • An open in the wire
    R2 BRN Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground (G501)
    • An open in the wire
    R5 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G502)
    • An open in the wire
    D4 LT GRN 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
    D5 WHT Trunk lid open Measure the voltage to ground There should be less than 1 V
    • Faulty trunk lid latch switch
    • Poor ground (G901)
    • An open in the wire
    Trunk lid closed Measure the voltage to ground There should be more than 5 V
    • Faulty trunk lid latch switch
    • A short to ground in the wire
    D12 BRN 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
    D15 GRY Left rear door lock knob switch in UNLOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G601)
    • Faulty left rear door lock knob switch
    • An open in the wire
    Left rear door lock knob switch in LOCK Measure the voltage to ground There should be more than 5 V
    • Faulty left rear door lock knob switch
    • A short to ground in the wire
    G3 GRN/BLK Hood open Measure the voltage to ground There should be less than 1 V
    • Faulty hood switch
    • Poor ground(G302)
    • An open 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
    Q18 WHT Ignition key inserted into the ignition switch Measure the voltage to ground There should be less than 1 V
    • Faulty ignition key switch
    • Poor ground(G503)
    • An open in the wire
    Ignition switch LOCK (0), and the 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

    Passenger's MICU 

  7. Turn the ignition switch to LOCK (0), and remove the right kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS )
  8. Disconnect passenger's under-dash fuse/relay box connectors A, C, E, and H
    NOTE: All connector views are wire side of female terminals
    Fig 2: Identifying Passenger's Under-Dash Fuse/Relay Box Connectors A, C, E, And H
    G05994895Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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
  10. With the connectors 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 11
    NOTE: Before testing, make sure the No 15 (10 A) fuse in the under-hood fuse/relay box is OK
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    A20 LT GRN Connect terminal A14 to terminal A20 (or A38), and terminal A38 (or A20)to body ground Check actuator operation The front passenger's door lock actuator should UNLOCK (or LOCK)
    • Faulty front passenger's door lock actuator
    • An open in the wire
    A38 RED
    H27 RED Connect terminal A14 to terminal H27 (or H1), and terminal H1 (or H27)to body ground Check actuator operation The right rear door lock actuator should LOCK (or UNLOCK)
    • Faulty right rear door lock actuator
    • An open in the wire
    H1 LT GRN
    C4 WHT Connect battery power to the terminal C4 momentarily Check keyless buzzer operation The keyless buzzer should sound
    • Faulty keyless buzzer
    • Poor ground(G302)
    • An open in the wire
  11. Reconnect the connectors to the passenger's under-dash fuse/relay box, and 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
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test-Desired result Possible cause if desired result is not obtained
    A9 RED Under all conditions Measure the voltage to ground There should be battery voltage
    • Blown No 1 (AS F/B) (40 A) fuse in the under-hood fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    A14 WHT Under all conditions Measure the voltage to ground-There should be battery voltage
    • Blown No 15 (10 A) fuse in the under-hood fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    A35 BRN Ignition switch ON (II) Measure the voltage to ground There should be battery voltage
    • Blown No 5 (7 5 A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    A36 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G505)
    • An open in the wire
    A37 BLK Under all conditions Measure the voltage to ground-There should be less than 0 5V
    • Poor ground(G505)
    • An open in the wire
    E15 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G201)
    • An open in the wire
    E16 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G201)
    • An open in the wire
    H7 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G651)
    • An open in the wire
    H25 LT GRN 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
    H3 GRN 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
    H22 GRY Right rear door lock knob switch in UNLOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G651)
    • Faulty right rear door lock knob switch
    • An open in the wire
    Right rear door lock knob switch in LOCK Measure the voltage to ground There should be more than 5 V
    • Faulty right rear door lock knob switch
    • A short to ground in the wire

    Door Multiplex Control Unit 

  12. Turn the ignition switch to LOCK (0), and open and close the driver's door, then remove the power window master switch (see REAR POWER WINDOW SWITCH TEST )
  13. Disconnect the 37P connector from the door multiplex control unit
    Fig 3: Identifying Door Multiplex Control Unit Connector Terminals
    G05994896Courtesy of AMERICAN HONDA MOTOR CO., INC.
  14. 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 all the terminals look OK, go to step 15
  15. With the connector still disconnected, do these input tests at the following connector
    • If any test indicates a problem, find and correct the cause, then recheck the system
    • If all the input test proves OK, go to step 16
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    27 BLU Disconnect the front passenger's power window switch 37 P connector Check for continuity between the door multiplex control unit 37P connector terminal No 27 and front passenger's power window switch 37P connector terminal No 29 There should be continuity An open in the wire
    Check for continuity to ground There should be no continuity A short to ground in the wire
    33 BLU Disconnect driver's under-dash fuse/relay box connector P (20P) Check for continuity between the door multiplex control unit 37P connector terminal No 33 and driver's under-dash fuse/relay box connector P (20P) terminal No 5 There should be continuity An open in the wire
    Check for continuity to ground There should be no continuity A short to ground in the wire
    35 PNK Disconnect driver's under-dash fuse/relay box connector P (20P) Check for continuity between the door multiplex control unit 37P connector terminal No 35 and driver's under-dash fuse/relay box connector P (20P) terminal No 6 There should be continuity An open in the wire
    Check for continuity to ground There should be no continuity A short to ground in the wire
  16. Reconnect the 37P connector to the door multiplex control unit, and do these input tests at the following connector
    • If any test indicates a problem, find and correct the cause, then recheck the system 17
    • If all the input tests prove OK, go to step
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    13 WHT Under all conditions Measure the voltage to ground There should be battery voltage
    • Blown No 15 (10 A) fuse in the under-hood fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    14 LT GRN Ignition switch ON (ID Measure the voltage to ground There should be battery voltage
    • Blown No 16 (7 5 A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    25 WHT Under all conditions Measure the voltage to ground There should be battery voltage
    • Blown No 24 (20 A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire
    32 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G501)
    • An open in the wire
    37 BLK Under all conditions Measure the voltage to ground There should be less than 0 5V
    • Poor ground(G502)
    • An open in the wire
    28 ORN Driver's door key cylinder switch in LOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G501)
    • Faulty driver's door key cylinder switch
    • An open in the wire
    Driver's door key cylinder switch in neutral or UNLOCK Measure the voltage to ground There should be more than 5 V
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    29 BRN Driver's door key cylinder switch in UNLOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G501)
    • Faulty driver's door key cylinder switch
    • An open in the wire
    Driver's door key cylinder switch in neutral or LOCK Measure the voltage to ground There should be more than 5 V
    • Faulty driver's door key cylinder switch
    • A short to ground in the wire
    30 YEL Driver's door lock knob switch in LOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G501)
    • Faulty driver's door lock knob switch
    • An open in the wire
    Driver's door lock knob switch in neutral or UNLOCK Measure the voltage to ground There should be more than 5 V
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    31 WHT Driver's door lock knob switch in UNLOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground (G501)
    • Faulty driver's door lock knob switch
    • An open in the wire
    Driver's door lock knob switch in neutral or LOCK Measure the voltage to ground There should be more than 5 V
    • Faulty driver's door lock knob switch
    • A short to ground in the wire

    Front Passenger's Power Window Switch 

  17. Turn the ignition switch to LOCK(O), and remove the front passenger's power window switch (see FRONT PASSENGER'S POWER WINDOW SWITCH REPLACEMENT )
  18. Disconnect the 37P connector from the front passenger's power window switch
    Fig 4: Identifying Front Passenger's Power Window Switch Connector Terminals
    G05994897Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. 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 20
  20. Reconnect the 37P connector to the front passenger's power window switch, and do 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 21
    TROUBLESHOOTING CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    25 GRN Under all conditions Measure the voltage to ground There should be battery voltage
    • Blown No 13 (20 A) fuse in the passenger's under-dash fuse/relay box
    • An open in the wire
    37 BLK Under all conditions Measure the voltage to ground There should be less than 0 5 V.
    • Poor ground (G505)
    • An open in the wire
    34 WHT Front passenger's door lock knob switch in UNLOCK Measure the voltage to ground There should be less than 1 V
    • Poor ground(G505)
    • Faulty front passenger's door lock knob switch
    • An open in the wire
    Front passenger's door lock knob switch in LOCK Measure the voltage to ground There should be more than 5 V
    • Faulty front passenger's door lock knob switch
    • A short to ground in the wire
  21. If multiple failures are found on more than one control unit, replace the driver's under-dash fuse/relay box (includes the driver's MICU) (see DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL/INSTALLATION ) If input failures are related to a particular control unit, replace the control unit
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