The Power Window Mechanism

The window lift mechanism on the driver's side is operated via the driver door module (DDM). The window lift mechanism on the passenger side is operated either via the passenger door module (PDM) or via the driver door module (DDM).

The window lift mechanisms in both rear doors can be operated via the driver door module (DDM). The window lift mechanisms in the front and rear doors can be operated when the ignition key is in position I or II. The power windows can be operated from when the ignition is switched off until one of the front doors is opened.

The driver door module (DDM) has four spring loaded switches which operate the individual front and rear windows.

The passenger door module (PDM) has a spring loaded switch which operates the window in the front passenger door. The switches in the driver door module (DDM) which control the rear windows can only be activated up or down. The rear windows move up or down for as long as the switch is activated.

The switches for the front windows have five positions which control the position of the window:

0)  Normal position where the function is passive.

1)  step 1 upwards, raises the window for as long as the button is activated.

2)  step 2 upwards, automatically fully closes the window (AUTO-UP).

-1)  step 1 downwards, lowers the window for as long as the button is activated.

-2)  step 2 downwards, fully opens the window automatically (AUTO-DOWN).

The rear windows are powered via the central electronic module (CEM). However they can be disabled using a child lock switch on the driver door module (DDM). When the child lock is activated, the rear windows cannot be operated from the rear seats. They can still be operated however from the driver door module (DDM).

The front window lift mechanisms have a Hall sensor which measures the rotation speed of each lift mechanism, allowing them to determine the position of the window. If a Hall sensor is not functioning in one of the window lift mechanisms, the AUTO-UP or AUTO-DOWN function for that window is not available. The power window lift mechanism, power window lift motor and Hall sensor form one unit and cannot be replaced separately.

The window lift mechanisms in the front doors have an inbuilt function to prevent trapping. When AUTO-UP is activated, the window lift mechanism detects whether there is any resistance, i. e. whether too much force is required to close the window. If so, the window stops and then lowers slightly. The anti-trapping system is active during AUTO-UP if the window is open more than 3 mm.

A diagnostic trouble code (DTC) is stored if for any reason the power window mechanism is unable to determine the window position. If this should happen, the power window mechanism must be re-initialized. This is carried out via a diagnostic function in VIDA (Volvo scan tool).

The passenger door module (PDM) and driver door module (DDM) have diagnostics for the window lift mechanisms and Hall sensors in the front doors.