Brake Pedal Travel Sensor

TRACTION CONTROL SYSTEM
On vehicles equipped with the optional traction control an additional low fluid level switch is used. This switch is located in the master cylinder reservoir and is used to monitor fluid level. This switch is normally CLOSED. When the fluid level drops below a certain level the switch OPENS. The ABS control module reads this input and turns ON the warning lamps.

Circuits B20 and B21 are used for the switch.

MARK IV ABS
The Mark IV ABS system uses a special vacuum booster and master cylinder. The booster used with the Mark IV is a new "0" lost travel reaction disc type booster with the addition of a pedal travel sensor (PTS). The PTS is a linear variable displacement transducer with seven steps which provide brake pedal position information to the Controller, Antilock Brake (CAB).