Checking Pressure Accumulator Check Valve

1. With engine off, depress brake pedal approximately 20 times to reduce system pressure.
2. Disconnect warning light switch electrical connector, then remove switch.
3. Attach pressure gauge with hollow bolt and copper washers to brake servo unit. Attach thick copper washer between brake servo unit and banjo fitting, then the thin copper washer between hollow bolt and banjo fitting.
4. Start engine, let idle until pressure gauge reads approximately 2030 psi, then turn ignition Off.
5. Pump brake pedal until pressure drops to 1957 psi.
6. If operating pressure drops below 1885 psi within 5 minutes, replace pressure accumulator.