One problem related to brake master cylinder has been reported for the 1996 Volvo 850. The most recently reported issues are listed below.
While driving applied the brakes and the vehicle will not stop. Driver pumped on the brakes and then the vehicle stopped. Took vehicle to dealer several times. The first time they replaced the master cylinder , and two months earlier, dealer replace the rear rotors. May01, 98, dealer rewired the braking system. The driver hears noise when the vehicle goes over a large bump.