At least 5 times strongly press the brake pedal with the engine off, then start the engine with the pedal depressed. The brake pedal at the same time the valley drops noticeably under the foot.
Otherwise, unscrew the vacuum hose from the hydraulic booster, start the engine. Place your finger on the end of the vacuum hose to check for vacuum.
If there is no vacuum: Check the tightness and integrity of the vacuum hose and, if necessary, replace the hose. Tighten all clamps.
1 Handle
2 Protective cap
3 Rubber washer
4 Pressure spring
5 push button
6 Handbrake lever
7 Guide
8 Holder
9 Retaining bracket
10 Tube clamp
11 Holder
If there is a vacuum: measure the vacuum and, if necessary, replace the hydraulic booster (work must be done at a service station).