4-41. RELAY QUICK RELEASE VALVE MAINTENANCE (Con't).
Connect two air lines (8) to sides of relay quick release valve (2).
Connect two air lines (8) to brake chambers (7).
Connect tractor EMERGENCY and SERVICE air couplings to semitrailer (see paragraph 2-12).
Fully pressurize semitrailer air system (see TM 9-2320-273-10 or TM 9-2320-283-10).
Perform OPERATING TEST (this paragraph).
Perform LEAKAGE TEST (this paragraph).