What this code means
B1140 may indicate a driver’s power window position detect circuit concern, where the system may not be correctly recognizing the driver’s window position.
What the vehicle may do
- The driver’s power window may operate but position-based functions can be affected.
- The system may store the code when the recognized window position does not match the actual window position.
Possible fault areas
- Possible master switch position learning concern
- Possible driver’s power window position detection concern
- Possible body electrical or door multiplex control involvement
Diagnostic path
What B1140 is looking at
On this Honda CR-V Hybrid, B1140 is for the driver’s power window position detect circuit. In plain terms, the door multiplex control unit and power window master switch may not agree with the actual driver’s window position. The driver’s window may still move, but the system can lose confidence in where that glass actually is, especially for position-based functions. The broad fault area here is the driver’s power window position detection through the master switch and its learned position information, not a general engine or emissions fault.
Do the preliminary checks first
Before focusing on B1140 by itself, start with the basic system checks. If other power window or body communication codes are present, check what they mean first. When there are multiple codes, handle the multiple-code B-CAN diagnostic path before chasing this one, because another fault can lead you into the wrong direction on the window position code.
Reset the master switch position learning
Once the earlier checks are clear, perform the reset for the power window master switch. That reset is the required work item in this diagnostic path for the master switch position detection issue. Don’t substitute a parts call here; the procedure at this point is to reset the master switch, then move into confirmation.
Confirm the window operation
For confirmation, turn the vehicle to ON mode. Then use the power window master switch to manually open and close the driver’s window. The point of this check is to make the system see the driver’s window movement after the master switch reset and confirm the diagnostic path has been completed in the proper order.
Takeaway
The key with B1140 is not to jump straight to a component. Check for other related codes first, reset the power window master switch as directed, and then confirm driver’s window operation manually from the master switch. For more diagnostic training, visit stepdiagnostics.com.
Final check
B1140 is best approached by checking related codes first, resetting the power window master switch as directed, and then confirming manual driver’s window operation.
For more guided automotive diagnostics, visit STEP Diagnostics.
