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Home >> Honda >> 2009 >> Pilot EX, 3.5 4 >> Repair and Diagnosis >> Body & Frame >> Seats >> Driver Position Memory System (DPMS) >> DTC Troubleshooting >> DTC B1846: Power Seat Front Up-Down Switch Circuit Malfunction
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DTC B1846: Power Seat Front Up-Down Switch Circuit Malfunction

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch to LOCK (0), and then back to ON (II).
  3. Operate the front up-down switch in each direction for more than 1 second.
  4. Check for DTCs with the HDS.

    Is DTC B1846 indicated? 

    YES  - Go to step  5.

    NO  - Intermittent failure, the system is OK at this time. Check for loose or poor connections. ■

  5. Turn the ignition switch to LOCK (0).
  6. Disconnect power seat control unit connector B (40P).
  7. Disconnect the power seat adjustment switch 12P connector.
  8. Check for continuity between body ground and power seat control unit connector B (40P) terminals No. 1, No. 4, and No. 5 individually.
    Fig 1: Checking Continuity Between Body Ground & Power Seat Control Unit Connector B (40P) Terminals 1, 4 & 5
    G05966692Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair a short to ground in the wire. ■

    NO  - Go to step  9.

  9. Check for continuity between these power seat control unit connector B (40P) terminals:
    • No. 1 and No. 4
    • No. 1 and No. 5
    • No. 4 and No. 5
    Fig 2: Checking Continuity Between Power Seat Control Unit Connector B (40P) Terminals
    G05966693Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair a short in the wire. ■

    NO  - Go to step  10.

  10. Test the power seat adjustment switch (see POWER SEAT ADJUSTMENT SWITCH TEST/REPLACEMENT  ).

    Is the switch OK? 

    YES  - Replace the power seat control unit (see Power Seat Control Unit Input Test/Replacement  ). ■

    NO  - Replace the power seat adjustment switch POWER SEAT ADJUSTMENT SWITCH TEST/REPLACEMENT . ■