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Control Unit Input Test

NOTE: Before troubleshooting, troubleshoot the multiplex integrated control system 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 (0).
  2. Remove the mounting bolts from the driver's power seat (see FRONT SEAT REMOVAL/INSTALLATION ), and carefully tip the seat back.
    NOTE: Be careful not to scratch the interior trim.
  3. Disconnect the 40P connector (A) and 18P connector (B) from the power seat control unit (C).
    Fig 1: Identifying 40P Connector And 18P Connector Of Power Seat Control Unit
    G06162961Courtesy 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 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.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A1
    .
    A22    		 BLK
    .
    YEL/WHT    		 Headrest switch ON (pressed) Check for continuity between terminals A1 and A22:
    There should be continuity.
    • Faulty headrest switch
    • An open in the wire
    Headrest switch OFF (released) Check for continuity between terminals A1 and A22:
    There should be no continuity.
    • Faulty headrest switch
    • A short to ground in the wire
    B12
    .
    B5    		 BLK
    .
    RED    		 Under all conditions Connect terminals B1 and B12, and terminals B5 and A9 momentarily:
    The headrest actuators should work.
    • Faulty headrest actuator
    • An open in the wire
  6. Reconnect connectors A (40P) and B (18P) to the control unit, and do these input tests at the connectors.
    • If any tests indicate a problem, find and correct the cause, then recheck the system.
    • If all tests prove OK, the power seat control unit must be faulty; replace it.
    WIRE TEST CONDITION REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A9 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
    A35 BLK/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
    A37 BLU 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
    B1 RED Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 20 (40 A) fuse in the under-hood fuse/relay box
    • Blown No. 16 (20 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
    B8 BLU Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 20 (40 A) fuse in the under-hood fuse/relay box
    • Blown No. 14 (20 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
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