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Home >> Acura >> 2004 >> MDX Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 67 (Multiplex Integrated Control System) >> Driver's MPCS Unit Input Test
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Driver's MPCS Unit Input Test

WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before testing the driver's MPCS unit, troubleshoot the multiplex integrated control unit first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A  ).
  1. Turn the ignition switch to LOCK(O).
  2. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  3. Disconnect driver's MPCS unit connectors A (40P) and B (14P).
    Fig 1: Identifying Driver'S MPCS Unit Connectors A (40P) And B (14P)
    G05487868Courtesy 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.
    INPUT TESTS REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A28 LT GRN Under all conditions (Under-dash fuse/relay box connector J (21P) disconnected Check for continuity between the A28 terminal and the under-dash fuse/relay box connector J (21P) Non 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
  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.
    INPUT TESTS REFERENCE

    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 (G401)
    • 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
    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
    • Faulty under-dash fuse/relay box
    • An open in the wire
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