Operation CHARM: Car repair manuals for everyone.

Hydraulic System: Testing and Inspection


Leak test under pressure

Special tools and equipment





VAG1310 or VAG131OA brake pressure gauge


Requirement
- Brake system (hydraulic unit, brake hoses, brake lines and brake calipers) operating properly and free of leaks

Testing
- Remove bleeder screw at one front brake caliper. Connect pressure gauge VAG131 0 or VAG131 OA and bleed.
- Insert brake pedal depressor between brake pedal and driver's seat. Apply pressure to brake pedal until gauge indicates pressure of 50 bar (725 psi).
- The pressure must drop by not more than 4 bar (58 psi) during the test period of 45 seconds
If the pressure drop is greater:
- Replace brake master cylinder.