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Home >> Acura >> 2012 >> RL >> Repair and Diagnosis >> Body & Frame >> Seats >> Driver Position Memory System (DPMS) >> DTC Troubleshooting >> DTC B1840: Steering Column Tilt Pulse Failure
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DTC B1840: Steering Column Tilt Pulse Failure

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 tilt switch in all directions for more than 2 second.
  4. Check for DTCs with the HDS.

    Is DTC B1840 indicated? 

    YES  -Go to step 5.

    NO  -Intermittent failure, the tilt position sensor is OK at this time. Check for loose or poor connections at the power tilt motor/position sensor connector and at the power tilt/telescopic steering control unit connector.

  5. Check for DTCs with the HDS.

    Is DTC B1841 also indicated? 

    YES  -Go to step  17.

    NO  -Go to step 6.

  6. Clear the DTCs with the HDS.
  7. Turn the ignition switch to LOCK (0), and then back to ON (II).
  8. Operate the tilt switch for 2 seconds, and check the tilt motor operation.

    Does the tilt motor run smoothly? 

    YES  -Go to step 9.

    NO  -Go to step  26.

  9. Turn the ignition switch to LOCK (0).
  10. Disconnect power tilt/telescopic steering control unit connector A (16P).
  11. Disconnect the power tilt motor/position sensor 6P connector.
  12. Check for continuity between power tilt/telescopic steering control unit connector A (16P) terminals No. 4, No. 12, and No. 16 and power tilt motor/position sensor 6P connector terminals No. 4, No. 5, and No. 6 respectively.
    Fig 1: Checking Continuity Between Connector (16P) Terminals No. 4, No. 12 And No. 16
    G07363668Courtesy 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 body ground and power tilt/telescopic steering control unit connector A (16P) terminals No. 4 and No. 12 individually.
    Fig 2: Checking Continuity Between Body Ground And Power Tilt/Telescopic Steering Control Unit Connector A (16P) Terminals No. 4 And No. 12
    G07363669Courtesy 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 tilt/telescopic steering control unit connector A (16P).
  15. Turn the ignition switch to ON (II).
  16. Measure the voltage between power tilt motor/position sensor 6P connector terminals No. 4 and No. 6 and between terminals No. 5 and No. 6.
    Fig 3: Measuring Voltage Between Power Tilt Motor/Position Sensor 6P Connector Terminals No. 4 And No. 6 And Between Terminals No. 5 And No. 6
    G07363670Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Faulty power tilt motor/position sensor, replace the steering column assembly (see STEERING COLUMN REMOVAL AND INSTALLATION ).

    NO  -If there is no voltage, replace the power tilt/telescopic steering control unit (see POWER TILT/TELESCOPIC STEERING CONTROL UNIT INPUT TEST/REPLACEMENT  ). If there is battery voltage, repair a short in the wire.

  17. Turn the ignition switch to LOCK (0).
  18. Disconnect power tilt/telescopic steering control unit connector A (16P).
  19. Disconnect the power tilt motor/position sensor 6P connector.
  20. Check for continuity between power tilt/telescopic steering control unit connector A (16P) terminals No. 2 and No. 16 and power tilt motor/position sensor 6P connector terminals No. 3 and No. 6 respectively.
    Fig 4: Checking Continuity Between Connector (16P) Terminals No. 2 And No. 16 And 6P Connector Terminals No. 3 And No. 6
    G07363671Courtesy 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. Disconnect the power telescopic motor/position sensor 8P connector.
  22. Check for continuity between power tilt motor/position sensor 6P connector terminal No. 3 and body ground.
    Fig 5: Checking Continuity Between Power Tilt Motor/Position Sensor 6P Connector Terminal No. 3 And Body Ground
    G07363672Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire.

    NO  -Go to step 23.

  23. Reconnect power tilt/telescopic steering control unit connector A (16P).
  24. Turn the ignition switch to ON (II).
  25. Measure the voltage between power tilt/telescopic steering control unit connector A (16P) terminals No. 2 and No. 16.
    Fig 6: Measuring Voltage Between Power Tilt/Telescopic Steering Control Unit Connector (16P) Terminals No. 2 And No. 16
    G07363673Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage when the tilt switch is operated? 

    YES  -Faulty power tilt motor/position sensor, replace the steering column assembly (see STEERING COLUMN REMOVAL AND INSTALLATION ).

    NO  -Replace the power tilt/telescopic steering control unit (see POWER TILT/TELESCOPIC STEERING CONTROL UNIT INPUT TEST/REPLACEMENT  ).

  26. Turn the ignition switch to LOCK (0).
  27. Disconnect power tilt/telescopic steering control unit connector B (8P).
  28. Disconnect the power tilt motor/position sensor 6P connector.
  29. Check for continuity between power tilt/telescopic steering control unit connector B (8P) terminals No. 7 and No. 8 and power tilt motor/position sensor 6P connector terminals No. 1 and No. 2 respectively.
    Fig 7: Checking Continuity Between Connector B (8P) Terminals No. 7 And No. 8 And Sensor 6P Connector Terminals No. 1 And No. 2
    G07363674Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 30.

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

  30. Check for continuity between body ground and power tilt motor/position sensor 6P connector terminals No. 1 and No. 2 individually.
    Fig 8: Checking Continuity Between Body Ground And Power Tilt Motor/Position Sensor 6P Connector Terminals No. 1 And No. 2
    G07363675Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire.

    NO  -Go to step 31.

  31. Test the tilt motor (see POWER TILT/TELESCOPIC STEERING MOTOR TEST  ).

    Is the motor OK? 

    YES  -Faulty power tilt motor/sensor, replace the steering column assembly (see STEERING COLUMN REMOVAL AND INSTALLATION ).

    NO  -Replace the steering column assembly (see STEERING COLUMN REMOVAL AND INSTALLATION ).