Brake Lamp Switch
WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2014 Volvo XC90, 2013 Volvo XC90, 2012 Volvo XC90, 2011 Volvo XC90, and 2010 Volvo XC90. 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.