A brake system includes a service brake and a parking brake that brake a vehicle including a lift axle capable of ascending and descending. The brake system further includes a brake blocker device and a controller that controls the brake blocker device. The brake blocker device blocks at least one of supply of compressed air to the service brake and supply of compressed air to the parking brake. The service brake and the parking brake act on the lift axle. The controller actuates the brake blocker device when the lift axle is at a lifted position.

A brake system includes a service brake and a parking brake that brake a vehicle including a lift axle capable of ascending and descending. The brake system further includes a brake blocker device and a controller that controls the brake blocker device. The brake blocker device blocks at least one of supply of compressed air to the service brake and supply of compressed air to the parking brake. The service brake and the parking brake act on the lift axle. The controller actuates the brake blocker device when the lift axle is at a lifted position.

A braking system for a machine includes a first valve assembly having a first electronically actuated proportional valve, and a second valve assembly having a second electronically actuated proportional valve. The braking system includes a first pressure sensor and a second pressure sensor disposed downstream of the first and second valve assemblies, respectively. The first and second pressure sensors are configured to determine a first pressure and a second pressure of a braking fluid from the first and second valve assembly. The braking system also includes a controller configured to receive a signal indicative of the first pressure and the second pressure of the braking fluid and compare the first pressure and the second pressure. The controller is configured to selectively actuate at least one of the first electronically actuated proportional valve and the second electronically actuated proportional valve to substantially equalize the first pressure and the second pressure.

An electrically controlled valve for electrically controlling air brakes by releasing pressurized air at a controlled rate. The electrically controlled valve is useful for connecting a trailer with air brakes to a standard electrical connector on a towing vehicle that provides a proportional braking signal. The proportional signal is sent to the electrically actuated valve and a controller within the valve process the signal. When electrically actuated valve receives the proportional braking signal from the towing vehicle representing no braking force, electrically actuated valve to produce no air pressure to the air brake. When the electrically actuated valve receives the proportional braking signal from the towing vehicle representing full braking force, the electrically actuated valve provides air to the air brakes corresponding to full braking force of the air brakes.

An electrically controlled valve for electrically controlling air brakes by releasing pressurized air at a controlled rate. The electrically controlled valve is useful for connecting a trailer with air brakes to a standard electrical connector on a towing vehicle that provides a proportional braking signal. The proportional signal is sent to the electrically actuated valve and a controller within the valve process the signal. When electrically actuated valve receives the proportional braking signal from the towing vehicle representing no braking force, electrically actuated valve to produce no air pressure to the air brake. When the electrically actuated valve receives the proportional braking signal from the towing vehicle representing full braking force, the electrically actuated valve provides air to the air brakes corresponding to full braking force of the air brakes.