Six problems related to brake antilock control unit/module have been reported for the 1996 Volvo 850. The most recently reported issues are listed below.
While applying the brakes the abs brake light appeared on the dashboard, and remained on. Following that the brake pedal went to the floor. This caused a loss of braking power. Consumer was able to maintain control of the vehicle and drove it home. Consumer contacted the dealer, and the mechanic determined that the abs modular unit needed replacement.
While driving abs light appeared on the dashboard and remained on. Consumer was able to maintain control of the vehicle and drove it to the dealer for inspection. Mechanic determined that abs pump motor needed to be replaced.
Hairline crack in circuit board on vehicle computer makes abs and tracs braking system inoperative. This is an intermittent problem and goes off if the vehicle is stopped and re-started. I talked to an independent Volvo repair shop and he indicated that he has replaced ten computer this year in boise, idaho this year on various Volvo models, years 1993 to 1998.
I noticed an odd noise which sounded like something rolling around in the back of the car, but nothing was. At time of state inspection, I alerted the inspectors. They felt something bumping from within the gas tank. I disassembled the floor coverings and inspection ports for fuel pump and gauge sender. I removed the gauge sender and looked into the tank and observed a plastic bowl-like object surrounding the fuel pump. I rocked the car and this bowl would slosh against the pump. This object appears to be a baffle to reduce sloshing around the pump. It would seem that it was intended to be glued in place, but has broken loose. I suppose that this would eventually damage pump or tank. A new tank will cost close to $400 which I will now order. Additional problem is intermittent failure of anti-lock brake/tracs system module.
Bad abs module.
Abs and "trac off" lights came on intermittently due to a defective abs control unit.