Common faults and solutions
After understanding the structure of the braking system, let’s take a look at the common faults that actually occur.
The braking failures of semi-trailers generally manifest themselves as: air leakage, dragging brakes, and locking, which are analyzed separately below.
Common fault phenomenon one
1: The air pressure is lower than 0.7MPa for a long time or obvious dragging occurs when the trailer is driving. The processing method is as follows:
a. Replace the front end of the vehicle and troubleshoot the tractor.
b. Check the source of air leakage by applying soapy water to eliminate “leakage at the handshake connection”, “leakage at the pipe joint”, “air leakage in the brake chamber”, “air leakage at the emergency relay valve”, “trailer ABS” The valve is leaking” and other possible faults.
If there is, you need to check whether water has entered the valve body or obvious rust can be seen. If this phenomenon occurs, it means that the filtration and drying effect of the trailer air pipeline is not good, and the valve body may need to be replaced.
Common fault phenomenon two
The trailer cannot be started after parking and keeps locking up. The processing method is as follows:
A. First unplug the ABS spiral cable to see if it can start normally to eliminate circuit problems.
B. Put the tractor in the inflated state, unplug the air pipe of the manual valve, and check whether the air pressure at the air outlet is normal (the air pressure should be very high in the inflated state).
C. Check whether the parking brake is released.
D. If there is no problem in the air line inspection, the mechanical failure of the axle should finally be checked.
In all braking states of the trailer braking system, the air supply pipeline is completely kept open in terms of safety design. The foot brake and parking brake of the tractor work by supplying air to the control pipeline.
