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Front Passenger's MPCS Unit Input Test

  1. Turn the ignition switch to LOCK (0).
  2. Remove the front passenger's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  3. Disconnect front passenger's MPCS unit (A) connectors A (28P) and B (14P).
    Fig 1: Identifying Front Passenger's MPCS Unit Connectors A (28P) And B (14P)
    G08055413Courtesy 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 all the input tests prove OK, go to step 6.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A4 GRY Under-dash fuse/relay box connector X (39P) and the moonroof control unit/motor 10P connector disconnected Check for continuity between terminal A4 and under-dash fuse/relay box connector X (39P) terminal No. 15: There should be continuity. An open or high resistance in the wire
    Check for continuity to ground: There should be no continuity. Short to ground in the wire
    A3 YEL Ignition switch ON (II), connect terminals A3 and B8 with a jumper wire. Check the right rear power window motor operation: The motor should run (the power window should go down).
    • Blown No. 26 (30 A) fuse in the under-dash fuse/relay box
    • Blown No. 3 (P/W) (50 A) fuse in the main under-hood fuse box
    • Blown No. 25 (20 A) fuse in the under-dash fuse/relay box
    • Faulty main under-hood fuse box
    • Faulty under-dash fuse/relay box
    • Poor ground (G606) or an open in the ground wire
    • Faulty power window relay
    • Faulty right rear power window switch
    • Faulty right rear power window motor
    • An open or high resistance in the wire
    A28 ORN Ignition switch ON (II), connect terminals A28 and B8 with a jumper wire. Check the right rear power window motor operation: The motor should run (the power window should go up).
    B1 RED Connect terminals B8 and B1, and terminals B7 and B14 with jumper wires. Check the front passenger's power window motor operation: The motor should run (the power window should go down).
    • Blown No. 26 (30 A) fuse in the under-dash fuse/relay box
    • Blown No. 3 (P/W) (50 A) fuse in the main under-hood fuse box
    • Faulty main under-hood fuse box
    • Faulty under-dash fuse/relay box
    • Poor ground (G507) or an open in the ground wire
    • Faulty front passenger's power window motor
    • An open or high resistance in the wire
    B7 BLU Connect terminals B8 and B7, and terminals B1 and B14 with jumper wires. Check the front passenger's power window motor operation: The motor should run (the power window should go up).
    A24.B2 WHT.LT BLU Front passenger's power window switch in AUTO position Check for continuity between the terminals: There should be continuity.
    • Faulty front passenger's power window switch
    • An open or high resistance in the wire
    Front passenger's power window switch released Check for continuity between the terminals: There should be no continuity.
    • Faulty front passenger's power window switch
    • A short to ground in the wire
    A24.B11 WHT.BRN Front passenger's power window switch in DOWN position Check for continuity between the terminals: There should be continuity.
    • Faulty front passenger's power window switch
    • An open or high resistance in the wire
    Front passenger's power window switch released Check for continuity between the terminals: There should be no continuity.
    • Faulty front passenger's power window switch
    • A short to ground in the wire
    A24.B13 WHT.WHT Front passenger's power window switch in UP position Check for continuity between the terminals: There should be continuity.
    • Faulty front passenger's power window switch
    • An open or high resistance in the wire
    Front passenger's power window switch released Check for continuity between the terminals: There should be no continuity.
    • Faulty front passenger's power window switch
    • A short to ground in the wire
    A22.B10 BLK.RED Front passenger's power window switch in DOWN position Check for continuity between the terminals: There should be continuity.
    • Faulty front passenger's power window switch
    • An open or high resistance in the wire
    Front passenger's power window switch released Check for continuity between the terminals: There should be no continuity.
    • Faulty front passenger's power window switch
    • A short to ground in the wire
    B10.B12 RED.GRN Under all conditions (except pressing the front passenger's power window switch DOWN position) Check for continuity between the terminals: There should be continuity.
    • Faulty front passenger's power window switch
    • An open or high resistance in the wire
    Front passenger's power window switch in DOWN position Check for continuity between the terminals: There should be no continuity.
    • Faulty front passenger's power window switch
    • A short to ground in the wire
  6. Reconnect the connectors, 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, replace the front passenger's MPCS unit, then go to step 7.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A7 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G506) or an open in the ground wire
    • An open or high resistance in the wire
    B14 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G507) or an open in the ground wire
    • An open or high resistance in the wire
    A2 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
    • Faulty 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 or high resistance in the wire
    B8 GRN 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 main under-hood fuse box
    • Blown No. 26 (30 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    B3 GRN Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Faulty front passenger's MPCS unit
    • An open or high resistance in the wire
    • A short to ground in the wire
    B4 ORN Ignition switch ON (II), and front passenger's power window moving up or down. Measure the voltage between B4 and B6 terminals: An analog voltmeter should alternate between 0 V and about 5 V (a digital voltmeter should read about 2.5 V while the window moves).
    • Faulty front passenger's power window switch
    • Faulty front passenger's MPCS unit
    • Faulty front passenger' s power window motor
    • An open or high resistance in the wire
    • A short to ground in the wire
    B5 LT GRN Ignition switch ON (II), and front passenger's power window moving up or down. Measure the voltage between B5 and B6 terminals: An analog voltmeter should alternate between 0 V and about 5 V (a digital voltmeter should read about 2.5 V while the window moves).
    B6 GRY In all ignition switch positions, disconnect the front passenger's power window motor 6P connector. Check for continuity to ground: There should be continuity.
    • Poor ground (G506) or an open in the ground wire
    • Faulty front passenger's MPCS unit
    • An open or high resistance in the wire
  7. Reset the power window control unit 
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