Brake Light Switch The brake switch is located on the pedal box and is operated by the brake pedal. The switch is a Hall effect switch which detects the position of the brake pedal and determines when the driver has applied the brakes. The switch is connected directly to the ECM. The brake switch consists of an inner sensor in an outer mounting sleeve. To ensure correct orientation, the sensor is keyed to the mounting sleeve and the mounting sleeve is keyed to the pedal mounting bracket. Mating serrations hold the sensor in position in the mounting sleeve. While the brakes are off, the tang on the brake pedal rests against the end of the sensor. When the brake pedal is pressed, the tang moves away from the sensor and induces a change of sensor output voltages. This is sensed by the ECM which detects that the brake pedal has been applied. The ECM uses the brake signal for the following: l To limit fuelling during braking l To inhibit/cancel cruise control if the brakes are applied. In the event of a brake switch failure, the following symptoms maybe observed: l Cruise control inactive l Increased fuel consumption.