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DTC B1140: Driver's Power Window Position Detect 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 ). Make sure you reset the power window control unit whenever you replace or substitute any power window parts (see RESETTING THE POWER WINDOW CONTROL UNIT ).
  1. Clear the DTCs with the HDS
  2. Turn the ignition switch to LOCK (0) and then back to ON (II), or press the engine start/stop button to select the OFF mode and then the ON mode
  3. Open and close the driver's power window by using the driver's switch manually
  4. Check for DTCs with the HDS

    Is DTC B1125 or B1126 indicated? 

    YES  -Troubleshoot the DTC B1125 or B1126 (see DTC TROUBLESHOOTING )

    NO  -Go to step 5

  5. Reset the power window control unit (see RESETTING THE POWER WINDOW CONTROL UNIT )
  6. Check for DTCs again with the HDS

    Is DTC B1140 indicated? 

    YES  -Go to step 7

    NO  -The system is OK at this time

  7. Substitute a known-good power window master switch
  8. Open and close the driver's power window by using the driver's switch manually
  9. Check for DTCs with the HDS

    Is DTC B1140 indicated? 

    YES  -Replace the driver's power window motor (see FRONT DOOR GLASS AND REGULATOR REPLACEMENT )

    NO  -Faulty door multiplex control unit, replace the power window master switch (see REAR POWER WINDOW SWITCH TEST )