Check of serviceability of functioning of the vacuum amplifier of brakes
030 - Vacuum gauge
051 - Tester
060 - Pedal force meter
1. Connect the vacuum gauge (030) to the brake booster, then with a few clicks on the foot brake pedal, release the vacuum in the vacuum path.
2. Connect the tester (051) to the service fitting, or to the brake caliper.
3. Connect a meter to the foot brake pedal (060).
4. Start the engine and sharply release the depressed gas pedal to create the required vacuum in the vacuum path (0.60÷0.80 atm).
5. If the vacuum immediately drops, or its depth is insufficient, you should check the condition of the sealing ring installed between the vacuum booster servo drive and the GTZ, the possibility of failure of the control valve in the vacuum line is also possible. Evaluate the condition of the non-return valve, as well as the lines and vacuum reservoir of the differential lock drive. On diesel models, check that the vacuum pump is working properly. Replace failed components.
6. While depressing the pedal with the required effort, read the tester reading. Compare measurement results with requirements Specifications.
7. Disconnect the meter (060), tester (051) and vacuum gauge (030).
8. Bleed the brake system (see Section Bleeding the brake system).
Note. Only the circuit of the brake mechanism of the corresponding wheel needs to be pumped.