Air brake doesn't work / Bad parking brake valve

The trailer was without service brake , driver was able to release the parking brake but the service brake were not working, and all this because the parking brake valve was broken and it were not allowing the air to go to the air tank, after we replaced the parking brake valve the tank was filled with air and the service brake started to work!!!
 More air brake system repair videos in the playlist on the link below:
Semi trailer Air Brake Valve troubles...
 Heavy duty repair videos in the playlist on the link below:
Eaton transmission and clutch removal

• #autos_vehicles
• #air_brake
• #bendix
• #haldex
• #no_parking_brake
• #no_service_brake
• #air_line
• #quick_release_valve
• #air_valve
• #parking_brake
• #service_brake
• #air_brake_system
• #semi_trailer_brake
• #truck_brake
• #brake_shoes
• #brake_chambers
• #drum
• #no_brakes
• #pressure_protection_valve
• #check_valve
• #abs_valve
• #heavy_duty_repair
• #valera_moscalu
• #tacoma
• #washington
• #10000