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Control Unit Input Test

  1. Turn the ignition switch to LOCK (0).
  2. Remove the mounting bolt 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: Disconnecting 40P Connector And 18P Connector From Power Seat Control Unit
    G07355231Courtesy 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.
    • 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.
      TEST CONDITION AND WIRE 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 or high resistance 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 or high resistance in the wire
    • Reconnect connectors A (40P) and B (18P) to the control unit, and do the following input tests.
    • 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.
    TEST CONDITION AND WIRE REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A9 BLK In all ignition switch positions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G601)
    • An open or high resistance in the ground wire
    B4
    B18
    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 or high resistance 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 or high resistance 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 or high resistance 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 or high resistance in the wire
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