What does 'Brake Servo System Function Limited' mean in Audi?

1 Answers
OFinn
07/30/25 10:21am
Audi dashboard displays 'Brake Servo System Function Limited' indicating a fault in the vehicle's braking system, such as excessive brake pad wear or water ingress. You may continue driving to see if the warning disappears. If it persists, it is recommended to visit a 4S store for code reading and troubleshooting. Below is an introduction to this system: 1. Overview: This braking system is formed by adding a power servo system to the manual hydraulic braking system. Under normal circumstances, most of the braking energy is supplied by the power servo system. In case of servo system failure, it can still rely entirely on the driver's input. 2. Types: Servo braking systems can be divided into two categories: booster type and supercharging type. The booster type, also known as direct control type, features a servo system control device (control valve) directly operated by the brake pedal mechanism. The vacuum servo chamber generates assistance that works together with pedal force on the brake master cylinder to supplement pedal force. Passenger vehicles commonly use vacuum booster servo braking systems.
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