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Control Unit Input Test

NOTE: Make sure the ignition switch is in LOCK (0) before disconnecting the under-dash fuse/relay box connectors.
  1. Before testing the entry light control functions, troubleshoot the multiplex integrated control system using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

    Multiplex Integrated Control Unit 

  2. Remove the left front door fill trim and left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Disconnect the under-dash fuse/relay box connectors E, H, P and W.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors Terminals
    G05968761Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Inspect the connector 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 under-dash fuse/relay box connectors still disconnected, 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 6.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    P7 WHT/BLK Under all conditions Attach to ground:
    Ignition key light should come on.
    • Blown No. 7 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty ignition key light (LED)
    • An open or high resistance in the wire
    W4 BLU/RED Under all conditions (Interior light switch in middle (DOOR) position) Attach to ground:
    Front and rear map light(s) should come on.
    • Blown No. 6 (10 A) fuse in the under-dash fuse/relay box
    • Blown bulb
    • Faulty map light
    • An open or high resistance in the wire
  6. Reconnect the 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 ground wire
    E9 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 ground wire
    E15 GRN Driver's door open Measure the voltage to ground:
    There should be less than 0.2 V.
    • Faulty driver's door switch
    • An open or high resistance in the wire
    Driver's door closed Measure the voltage to ground:
    There should be about 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 0.2 V.
    • Faulty front passenger's door switch
    • An open or high resistance 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 0.2 V.
    • Faulty left rear door switch
    • An open or high resistance in the wire
    Left rear door closed Measure the voltage to ground:
    There should be about 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 0.2 V.
    • Faulty right rear door switch
    • An open or high resistance in the wire
    Right rear door closed Measure the voltage to ground:
    There should be about 5 V.
    • Faulty right rear door switch
    • A short to ground 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) position 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

    Door Multiplex Control Unit 

  7. Turn the ignition switch to LOCK (0).
  8. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  9. Disconnect the 23P connector from the power window master switch.
  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.
    Fig 2: Identifying Door Multiplex Control Unit 23P Connector Terminals
    G05968762Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Reconnect the connector to the power window master switch. 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, the MICU must be faulty; replace the under-dash fuse/relay box (see UNDER-DASH FUSE/RELAY BOX ).
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    7 WHT/BLK Driver's door lock knob switch in UNLOCK 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 in LOCK Measure the voltage to ground:
    There should be about 5 V.
    • Faulty driver's door lock knob switch
    • A short to ground in the wire
    22 YEL/RED Driver's door lock knob switch in LOCK 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 in UNLOCK Measure the voltage to ground:
    There should be about 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 about 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 about 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 about 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 about 5 V.
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