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Driver's MPCS Unit Input Test

  1. Turn the ignition switch OFF.
  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 (14P).
    Fig 1: Identifying MPCS Unit Connectors (40P) And (14P)
    G05497074Courtesy 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.
    TEST CONDITION AND POSSIBLE CAUSE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A8 GRY Driver's under-dash fuse/relay box connector H (14P) and power window master switch 6P connector disconnected Check for continuity between the A8 terminal and driver's under-dash fuse/relay box connector H (14P) No. 4 terminal, and A8 terminal and power window master switch 6P connector No. 6 terminal:
    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
    B10 PUR 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
    B12 ORN
    B10 PUR Driver's power window switch released Check for continuity between the terminals:
    There should be continuity.
    • Faulty power window master switch
    • An open in the wire
    B12 ORN
    B10 PUR 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
    B13 PNK
    B10 PUR 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
    B13 PNK
    B9 LTGRN 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
    B2 LTBLU
    B9 LTGRN 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
    B2 LTBLU
    B1 LTGRN Connect the B8 and B1 terminals with a jumper wire, and connect the B7 terminal to body ground. Check the driver's power window motor operation:
    The motor should run (the window should go down).
    • Blown No. 27 (30A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's power window motor
    • An open in the wire
    B7 BLU Connect the B8 and B7 terminals with a jumper wire, and connect the B1 terminal to body ground. Check the driver's power window motor operation:
    The motor should run (the window should go up).
    • Blown No. 27 (30A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's power window motor
    • An open in the wire
  6. Reconnect the connectors to the driver's MPCS unit, 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, the control unit must be faulty; replace the driver's MPCS unit and go to step 7.
    TEST CONDITION AND POSSIBLE CAUSE REFERENCE 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 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
    A7 WHT Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 15 (40A) fuse in the under-hood fuse/relay box
    • Blown No. 7 (10A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's 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. 23 (P/W) (50A) fuse in the under-hood fuse/relay box
    • Blown No. 27 (30A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's 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 (10A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • 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
    • A short to ground in the wire
    B3 RED Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Faulty driver's MPCS unit
    • An open in the wire
    B6 GRN Under all conditions Measure the continuity to ground:
    There should be continuity.
    • Poor ground (G601)
    • Faulty driver's MPCS unit
    • 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 with a jumper wire, and connect the B7 terminal to body ground. 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 window moves).
    • Blown No. 27 (30A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's MPCS unit
    • Faulty driver's power window motor
    • 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 with a jumper wire, and connect the B7 terminal to body ground. 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 window moves).
    • Blown No. 27 (30A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's MPCS unit
    • Faulty driver's power window motor
    • An open in the wire
  7. Reset the power window control unit (see RESETTING THE POWER WINDOW CONTROL UNIT  ).
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