Pressure Accumulator Check Valve, Checking For Leaks
- No leaks in brake servo
Checking
-- Connect hose of tester Pressure Gauge:VAG1441 to hydraulic brake servo using banjo bolt and copper seals that come with tester.
-- Let engine idle until maximum pressure is reached.
-- Stop engine.
-- Reduce pressure to approx. 135 bar (1958 psi) by operating brake pedal a number of times.
After approx. 5 minutes, the pressure may fall to maximum 130 bar (1885 psi).
If pressure drop is greater, pressure accumulator check valve leaks:
-- Replace pressure accumulator.
-- Reduce operating pressure by pumping brake pedal approx. 20 times with engine not running.
-- Remove tester Pressure Gauge:VAG1441 .
-- Install warning switch and check for leaks.
-- Check hydraulic fluid, top off if necessary