In this tutorial you will learn how to perform a tractor protection valve test. _______ New videos every Tuesday and Thursday! Like, comment, and subscribe for more training videos.
You need to supply air to the trailer and perform the same test the valve also protects the truck from trailer break away and between 20 and 45 psi the trailer valve should then pop back out saving some air for safe braking of the tractor
That is the "brake control valve" the part in the dash. This video is testing the "tractor protection valve" which is usually mounted to the back of the cab where the glad hand hoses connect on the tractor. The tractor protection valves only job is to stop air from going to the trailer service line when you are using your service brakes while bob-tailing. Also when the valves pop out on the dash that means the spring brakes are now engaged so the wheels/axles with spring brakes installed will be ideally locked up... that's not exactly safe braking.
