One problem related to brake hoses, lines/piping, and fittings has been reported for the 2000 Volvo S40. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2000 Volvo S40 based on all problems reported for the 2000 S40.
In the last 6 months I have lost total braking ability 3 times while driving. The dealer is sighting a broken t-connector on a low pressure hose as the problem. Contacted the regional customer service. After 3rd time, without root cause analysis they said that they would replace with a brass t-connector, which to date they can not find. They consider the car safe to drive since brakes work currently, however they failed without warning the last 2 times. I was lucky enough to be in places where no accident occured. I did roll through a toll booth, stop sign on the first two occurances. Dealer will not reveal if this is a design defect, parts defects or something specific in this automobile. This car is not safe to drive on the road but Volvo seems to not take it seriously.