Brake Master Cylinder Reservoir with Brake Master Cylinder Fluid Level Sensor

The brake master cylinder sensor is an integral part of the brake master cylinder reservoir. It is serviced as a part of the brake master cylinder reservoir. It consists of a float containing a magnet and a reed switch mounted in the bottom of the brake master cylinder reservoir. When the fluid in the brake master cylinder reservoir gets to a predetermined level, the floating magnet actuates the reed switch, causing the warning lamp to light. Loss of fluid from either the primary (front) or secondary (rear) system will cause this system to actuate.

If the brake master cylinder sensor is inoperative, the brake master cylinder reservoir must be replaced.