Technician Safety Information
Some service procedures require that the hydraulic lines, hoses, and fittings be disconnected. The system uses a hydraulic accumulator that, when fully charged contains brake fluid under high pressure. Be sure the accumulator is fully discharged when disconnecting lines, hoses, and fittings. Failure to do so will result in personal injury or damage to painted services.
Use only DOT 3 fluid from a sealed container. Using DOT 5 fluid may cause damage to systems components.
Before suspecting the ABS system is the fault of degraded braking performance check all items that would be associated with a NON-ABS system. This includes the inspection of brake linings, brake rotors and drums, inspecting for fluid leaks, and thorough inspection of brake components.
Certain conditions can result in reduced braking ability. Take this in consideration when driving a vehicle that may have a fault in the ABS system.
Pressure bleeding equipment must have a rubber diaphragm between the air supply and brake fluid. This will prevent outside air, moisture, oil, and other contaminants from entering the hydraulic brake system.
THE FOLLOWING INFORMATION HAS BEEN UPDATED BY TSB # 87-C-05, JULY 2, 1987
General Motors has determined that a defect which relates to vehicle safety may exist in some 1986 and 1987 Ninety Eight Regencys.
Involved vehicles may exhibit brake fluid seepage from the ABS pressure warning switch which can eventually lead to loss of the brake system hydraulic pump motor. Loss of the hydraulic pump motor would, after accumulator pressure has been depleted (approximately 10-30 normal stops) result in total loss of rear brakes as well as power assist to to the front brakes. The red "BRAKE" would, before accumulated pressure has been depleted, illuminate and stay ON. If this warning is not headed, a loss of brakes at a time when minimum stopping distance is required could result in a vehicle crash.
For more information regarding the diagnosis and servicing of this malfunction see TSB #87-C-05.