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Home >> Acura >> 2011 >> RDX 2.3 TB2 >> Repair and Diagnosis >> Body & Frame >> Seats >> Driver Position Memory System (DPMS) >> DTC Troubleshooting >> DTC B1826: Front Height Pulse Error (no change in pulse for 1 second)
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DTC B1826: Front Height Pulse Error (no change in pulse for 1 second)

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 power seat adjustment switch in all directions for more than 2 seconds each.
    NOTE: DTC B1826 is stored when the front up-down switch is operated more than 1 second after the seat moves to the most up or most down position, even when the system is OK.
  4. Check for DTCs with the HDS.

    Is DTC B182.6 indicated? 

    YES  -Go to step 5.

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

  5. Clear the DTCs with the HDS.

    Is DTC B1836 also indicated? 

    YES  -Go to the DTC B1836 troubleshooting (see DTC B1836: POWER SEAT POSITION SENSOR CIRCUIT SHORT  ).

    NO  -Go to step 6.

  6. Clear the DTCs with the HDS.

    Are DTCs B1825, B1827, and/or B1828 also indicated? 

    YES  -Go to step  17.

    NO  -Go to step 7.

  7. Turn the ignition switch to LOCK (0) and then back to ON (II).
  8. Operate the front up-down switch for 2 seconds, and check the front up-down motor operation.

    Does the front up-down motor run smoothly? 

    YES  -Go to step 9.

    NO  -Go to step  24.

  9. Turn the ignition switch to LOCK (0).
  10. Disconnect power seat control unit connector A (40P).
  11. Disconnect the front up-down motor/position sensor 5P connector.
  12. Check for continuity between power seat control unit connector A (40P) terminals No. 12, No. 15, and No. 29 and the front up-down motor/position sensor 5P connector terminals No. 3, No. 4, and No. 5 respectively.
    Fig 1: Checking Continuity Between Power Seat Control Unit Connector A (40P) Terminals 12 And Front Up-Down Motor/Position Sensor 5P Connector Terminals 3
    G08061440Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 13.

    NO  -Repair an open or high resistance in the wire.

  13. Check for continuity between power seat control unit connector A (40P) terminal No. 12 and body ground.
    Fig 2: Checking Continuity Between Power Seat Control Unit Connector A (40P) Terminal No. 12 And Body Ground
    G08061441Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire.

    NO  -Go to step 14.

  14. Reconnect power seat control unit connector A (40P).
  15. Turn the ignition switch to ON (II).
  16. Measure the voltage between the front up-down motor/position sensor 5P connector terminals No. 5 (+) and No. 4(-).
    Fig 3: Measuring Voltage Between Front Up-Down Motor/Position Sensor 5P Connector Terminals No. 5 (+) And No. 4(-)
    G08061442Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Replace the seat frame assembly (see FRONT SEAT FRAME REPLACEMENT - DRIVER'S SEAT ).

    NO  -If there is no voltage, replace the power seat control unit (see POWER SEAT CONTROL UNIT INPUT TEST/REPLACEMENT  ). If there is battery voltage, repair a short in the wire (sensor line).

  17. Turn the ignition switch to LOCK (0).
  18. Disconnect power seat control unit connector A (40P).
  19. Disconnect the front up-down motor/position sensor 5P connector.
  20. Check for continuity between power seat control unit connector A (40P) terminals No. 15 and No. 29 and front up-down motor/position sensor 5P connector terminals No. 3 and No. 4 respectively.
    Fig 4: Checking Continuity Between Power Seat Control Unit Connector A (40P) Terminals 15 And Front Up-Down Motor/Position Sensor 5P Connector Terminals 3
    G08061443Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 21.

    NO  -Repair an open or high resistance in the wire.

  21. Reconnect power seat control unit connector A (40P).
  22. Turn the ignition switch to ON (II).
  23. Measure the voltage between power seat control unit connector A (40P) terminals No. 15 and No. 29.
    Fig 5: Measuring Voltage Between Power Seat Control Unit Connector A (40P) Terminals No. 15 And No. 29
    G08061444Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage when the front up-down switch is operated? 

    YES  -Replace the seat frame assembly (see FRONT SEAT FRAME REPLACEMENT - DRIVER'S SEAT ).

    NO  -Replace the power seat control unit (see POWER SEAT CONTROL UNIT INPUT TEST/REPLACEMENT  ).

  24. Check the No. 14(20 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step 25.

    NO  -Replace the fuse. If the fuse is blown again, repair the short to ground in the No. 14(20 A) fuse circuit.

  25. Disconnect under-hood fuse/relay box connector E (10P).
  26. Disconnect power seat control unit connector B (18P).
  27. Check for continuity between under-hood fuse/relay box connector E (10P) terminal No. 9 and power seat control unit connector B (18P) terminal No. 8.
    Fig 6: Checking Continuity Between Under-Hood Fuse/Relay Box Connector E (10P) Terminal 9 And Power Seat Control Unit Connector B (18P) Terminal 8
    G08061445Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 28.

    NO  -Repair an open or high resistance in the wire.

  28. Reconnect power seat control unit connector B (18P).
  29. Measure the voltage between power seat control unit connector B (18P) terminal No. 18 and body ground when operate the front up-down switch.
    Fig 7: Measuring Voltage Between Power Seat Control Unit Connector B (18P) Terminal No. 18 And Body Ground
    G08061446Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there more than 0.2 V? 

    YES  -Repair an open or high resistance in the ground wire or poor ground (G551).

    NO  -Go to step 30.

  30. Turn the ignition switch to LOCK (0).
  31. Disconnect power seat control unit connector B (18P).
  32. Disconnect the front up-down motor/position sensor 5P connector.
  33. Check for continuity between power seat control unit connector B(18P) terminals No. 6 and No. 16 and front up-down motor/position sensor 5P connector terminals No. 2 and No. 1 respectively.
    Fig 8: Checking Continuity Between Power Seat Control Unit Connector B(18P) Terminals 6 And Front Up-Down Motor/Position Sensor 5P Connector Terminals 2
    G08061447Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 34.

    NO  -Repair an open or high resistance in the wire.

  34. Check for continuity between body ground and front up-down motor/position sensor 5P connector terminals No. 1 and No. 2 individually.
    Fig 9: Checking Continuity Between Body Ground And Front Up-Down Motor/Position Sensor 5P Connector Terminals No. 1
    G08061448Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire.

    NO  -Go to step 35.

  35. Test the front up-down motor (see DRIVER'S POWER SEAT MOTOR TEST  ).

    Is the motor OK? 

    YES  -Replace the power seat control unit (see POWER SEAT CONTROL UNIT INPUT TEST/REPLACEMENT  ).

    NO  -Replace the seat frame assembly (see FRONT SEAT FRAME REPLACEMENT - DRIVER'S SEAT ).

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