One problem related to service brakes has been reported for the 1999 Volvo S80. The most recently reported issues are listed below.
I've had this problem for months now. The car shuts down and won't restart! I been taking off the battery and letting it sit over night, then putting cables back on to get it to restart! today I drove it for a mile and parked it and while it was running it shut down again! most of the time it shuts down when I'm driving and I lose brake control!.