Parking brake warning system for air brakes

A parking brake warning system for vehicles equipped with air brakes, comprising:

• a parking brake switch connected to an air line that is configured to control a supply of air pressure to a vehicle parking brake for application of the vehicle parking brake;
• wherein activation of the parking brake switch substantially evacuates the air line, and
• deactivation of the parking brake switch pressurizes the air line;
• a pressure switch connected to the air line, the pressure switch being closed when the air line is pressurized, and open when the pressure of the air line is below a given threshold pressure, the pressure switch including a T-shaped fitting configured to permit splicing of the pressure switch into the air line;
• at least one warning module adapted to provide an alert, the at least one warning module being in electrical connection with the pressure switch;
• a power source in electrical connection with the least one warning module;
• a door jamb switch configured to be closed when a vehicle door is open, and open when a vehicle door is closed;
• and
• a ground;
• whereby the pressure switch and the door jamb switch are electrically connected in series and are adapted to complete a circuit between the power source, the at least one warning module, and the ground when the pressure switch and the door jamb switch are both closed.

A kit for installing a parking brake warning system for vehicles equipped with air brakes, comprising:

• a low pressure switch adapted to be connected to a vehicle air line, the low pressure switch being closed when the air line is pressurized, and open when the air line is evacuated, the low pressure switch including a T-shaped fitting configured to permit splicing of the low pressure switch into the air line;
• at least one warning module adapted to provide an alert, the at least one warning module adapted to be in electrical connection with the low pressure switch;
• a door jamb switch configured to be closed when a vehicle door is open, and open when a vehicle door is closed;
• wiring and connectors for electrically connecting the at least one warning module to a vehicle power source;
• and
• wiring and connectors for electrically connecting the low pressure switch in series with the door jamb switch and a vehicle ground.