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Driver's MPCS Unit Input Test

  1. Turn the ignition switch to LOCK (0).
  2. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  3. Disconnect driver's MPCS unit (A) connectors A (40P) and B (UP).
    Fig 1: Identifying Driver's MPCS Unit Connectors Terminals
    G05488047Courtesy 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, make these input tests at the 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.
    CAVITY AND TEST CONDITION CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A8 GRY Under-dash fuse/relay box connector J (21P) and power window master switch connector B (14P) disconnected Check for continuity between the A8 terminal and under-dash fuse/relay box connector J (12P) No. 1 terminal, and A8 terminal and power window master switch connector B (14P) No. 13 terminal:
    There should be continuity.    		 An open in the wire
    Check for continuity to ground:
    There should be no continuity.    		 Short to ground in the wire
    A39 WHT Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 3 (P/W) (50 A) fuse in the main under-hood fuse box
    • Faulty power window relay
    • An open in the wire
    A3 ORN Connect the A39 terminal to body ground, and connect the A3 and B8 terminals with a jumper wire. Check the left rear power window motor operation:
    The motor should run (the power window should go up).
    • Blown No. 24 (20 A) fuse in the under-dash fuse/relay box
    • Poor ground (G601)
    • Faulty power window relay
    • Faulty left rear power window switch
    • Faulty left rear power window motor
    • An open in the wire
    A32 YEL Connect the A39 terminal to body ground, and connect the A32 and B8 terminals with a jumper wire. Check the left rear power window motor operation:
    The motor should run (the power window should go down).
    B1 YEL Connect the B8 and B1 terminals, and the B7 and B14 terminals with jumper wires. Check the driver's power window motor operation:
    The motor should run (the power window should go down).
    • Blown No. 27 (30 A) fuse in the under-dash fuse/relay box
    • Faulty driver's power window motor
    • An open in the wire
    B7 BLU Connect the B8 and B7 terminals, and the B1 and B14 terminals with jumper wires. Check the driver's power window motor operation:
    The motor should run (the power window should go up).
    B9
    - - -
    B2    		 LT GRN
    - - -
    GRN    		 Driver's power window switch in UP position Check for continuity between the terminals:
    There should be continuity.
    • Faulty power window master switch
    • An open in the wire
    Driver's power window switch released Check for continuity between the terminals:
    There should be no continuity.
    • Faulty power window master switch
    • A short to ground in the wire
    B10
    - - -
    B12    		 PUR
    - - -
    ORN    		 Under all condition (except pressing the driver's power window switch DOWN position) Check for continuity between the terminals:
    There should be continuity.
    • Faulty power window master switch
    • An open in the wire
    Driver's power window switch in DOWN position Check for continuity between the terminals:
    There should be no continuity.
    • Faulty power window master switch
    • A short to ground in the wire
    B10
    - - -
    B13    		 PUR
    - - -
    RED    		 Driver's power window switch in DOWN position Check for continuity between the terminals:
    There should be continuity.
    • Faulty power window master switch
    • An open in the wire
    Driver's power window switch released Check for continuity between the terminals:
    There should be no continuity.
    • Faulty power window master switch
    • A short to around in the wire
  6. Reconnect the connectors, and make these input tests at the connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, replace the driver's MPCS unit, then go to step 7.
    CAVITY AND TEST CONDITION CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A5 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
    B14
    A7 WHT Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 4 (40 A) fuse in the main under-hood fuse box
    • Blown No. 7 (10 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open in the wire
    B8 WHT Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 3 (P/W) (50 A) fuse in the main under-hood fuse box
    • Blown No. 27 (30 A) fuse in the under-dash fuse/relay box
    • An open in the wire
    A25 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 in the wire
    B3 PNK Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Faulty driver's MPCS unit
    • An open in the wire
    B4 BRN Ignition switch ON (II), and driver's power window motor runs by connecting the B8 and B1 terminals and the B7 and B14 terminals with jumper wires. Measure the voltage between the B4 and B6 terminals:
    There should be 0-about 5 V - 0- about 5 V repeatedly (a digital voltmeter reads about 2.5 V while the power window moves).
    • Blown No. 27 (30 A) fuse in the under-dash fuse/relay box
    • Faulty driver's MPCS unit
    • Faulty driver's power window motor
    • An open in the wire
    B5 GRY Ignition switch ON (II), and driver's power window motor runs by connecting the B8 and B1 terminals and the B7 and B14 terminals with jumper wires. Measure the voltage between the B5 and B6 terminals:
    There should be 0-about 5 V - 0- about 5 V repeatedly (a digital voltmeter reads about 2.5 V while the power window moves).
    • Blown No. 27 (30 A) fuse in the under-dash fuse/relay box
    • Faulty driver's MPCS unit
    • Faulty driver's power window motor
    • An open in the wire
    B6 WHT Ignition switch ON (II) Check for continuity to ground:
    There should be continuity.
    • Poor ground (G601)
    • Faulty driver's MPCS unit
    • An open in the wire
    B9 LT GRN Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Faulty driver's MPCS unit
    • Faulty power window master switch
    • An open in the wire
    • A short to ground in the wire
  7. Reset the power window control unit (see RESETTING THE POWER WINDOW CONTROL UNIT  ).
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