Home › CDL Practice Tests › Air Brakes Questions › Question 35
If tank pressure keeps rising well past governor cut-out toward 150 psi, what is the most likely fault?
- A.The brake linings are too thick
- B.The governor or compressor unloading mechanism is not working correctly
- C.The slack adjusters are too short
- D.The gladhand seals are new
Correct answer
B. The governor or compressor unloading mechanism is not working correctly
Why
Normal control should stop pumping at cut-out, so continued rise means the governor signal or unloader has failed. The safety valve will vent the excess, but the vehicle needs repair rather than continued operation.
Manual topic: Air Brakes - Air Compressor and Governor · From the Air Brakes practice bank (AB-035).