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Driver's MPCS Unit Input Test

NOTE: Before testing, troubleshoot B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  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 connector A (40P).
    Fig 1: Identifying Driver's MPCS Unit Connector A (40P) Terminals
    G06162698Courtesy 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. Reconnect the connector to the driver's MPCS unit, and make these input tests at the connector.
    • 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 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 0.1 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 (40 A) fuse in the under-hood fuse/relay box
    • Blown No. 7 (10 A) fuse in the 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 (10 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
  6. Disconnect driver's MPCS connector A (40P), and make these input tests at the connector.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the driver's MPCS unit must be faulty, replace it.
    TEST CONDITION CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A8 GRY Under all conditions (Driver's under-dash fuse/relay box connector J (21P), power window master switch 6P connector, and moonroof motor/control unit 10P connector disconnected) Check for continuity between the A8 terminal and driver's under-dash fuse/relay box connector J (21P) terminal No. 1, A8 terminal and power window master switch 6P connector No. 6 terminal, and A8 terminal and moonroof motor/control unit 10P connector terminal No. 4: 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
    A28 LT GRN Under all conditions (Driver's under-dash fuse/relay box connector J (21P)and AcuraLink control unit (XM receiver) connector A (32P) disconnected) Check for continuity between the A28 terminal and driver's under-dash fuse/relay box connector J (21P) terminal No. 4, and A8 terminal and AcuraLink control unit (XM receiver) connector A (32P) terminal No. 10: 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
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