There is no such thing as a nomalization process on E53 door windows. The front window motors are directly controlled by the front door modules and depending on input from the drivers window switch, the body module will send a signal over the P-BUS to control the passenger front door module, and these door modules are otherwise known as the window switch blocks. The rear door windows are directly controlled by the body module.

Each door has a pressure switch at the top of the window frame. When an object or appendage is blocking the window from closing properly, the anti-trap function will occur and the window motor will operate in reverse to free the object or appendage. Because of this anti-trap switch, this vehicle does not need initilzation for door windows.

The door module or body module knows when to stop the motor as an increase in amperage from the motor will signal end of travel. If however, the door module or body module cannot decipher an increase in amperage, the modules are programmed to stop the window motors after 6-8 seconds.

If the door modules or body modules internal relays are faulted, it may continue to operate the window motor until the motor has burned out. The most common fault is the front passenger window switch.