Headlamp range adjustment (certain markets)
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2007 Volvo V70, 2006 Volvo V70, 2005 Volvo V70, 2004 Volvo V70, and 2003 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.
Headlamp range adjustment is controlled by the central electronic module (CEM) (4/56). The central electronic module (CEM) communicates with the light switch module (LSM) (3/111) using serial communication.
If the thumb wheel in the light switch module (LSM) is turned, information about the position of the wheel is transmitted to the central electronic module (CEM). The central electronic module (CEM) transmits a pulse width modulation (PWM) signal to the actuator motors (6/38-39) with the pulse ratio set according to the position of the thumb wheel. The headlamp range can be adjusted in 16 stages.