Brake Lamp Switch
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Volvo S80, 2005 Volvo S80, 2004 Volvo S80, 2003 Volvo S80, and 2002 Volvo S80. However, it is still accessible from the selected car via links, so may be relevant.
The brake lamp switch is a single pole switch positioned at the brake pedal lever. The brake lamp switch self-adjusts during installation.
The brake control module (BCM) receives information about the status of the brake lamp switch via the engine control module (ECM). The brake lamp switch signal is used by the brake control module (BCM) to diagnose faults in the pedal position sensor.
The brake lamp switch is supplied with power from the battery. When the switch is closed, the signal is grounded through the engine control module (ECM). The engine control module (ECM) then transmits a signal on the Control area network (CAN) indicating that the brake lamp switch has been activated.
There are diagnostics for the brake lamp switch.