Brake Fluid Accumulator: Description and Operation

Early Production ABS Operation

A hydraulic accumulator is used to store brake fluid at high pressure so that a supply of pressurized fluid is available for power assisted normal braking and anti-lock operation. Under normal operation, the pump/motor assembly charges the accumulator to an operating pressure of approximately 2100-2600 psi. Thus, it is extremely important that the recommended precautions be followed when servicing the Anti-lock Brake System (ABS) to prevent personal injury and/or damage to painted surfaces. The accumulator uses a sliding piston configuration with a nitrogen precharge of approximately 800 psi.

WARNING: The hydraulic accumulator is a nonserviceable component. Removal or disassembly may result in personal injury and/or improper system operation. The hydraulic accumulator and certain portions of the brake system contain brake fluid and nitrogen gas at high pressure. When servicing components of the hydraulic system, follow the procedures to depressurize the accumulator (see MAINTENANCE PROCEDURES).