Brake System Warning Light on a Audi S5
Stop safely as soon as possible. Continuing to drive risks serious damage or a safety hazard.
What the Brake System Warning Light Means on a Audi S5
On the Audi S5, the red brake light means the system has detected something wrong with your primary brakes — low fluid, a leak, or worn components pulling fluid level down. Unlike the ABS light, this one can affect your ability to stop.
How Urgent Is the Brake System Warning Light?
In terms of priority, treat this as a critical concern on your Audi S5. The single most useful thing you can observe is whether the Brake System Warning Light is steady or blinking: a steady light generally allows a careful drive to a safe location or a workshop, whereas a flashing light signals an active fault that can cause damage if you continue. Pay attention to changes in how the Audi S5 drives, sounds, or smells, since those symptoms sharpen the diagnosis considerably.
Common Symptoms Alongside the Brake System Warning Light
When the Brake System Warning Light shows up on a Audi S5, it rarely arrives completely alone — there are usually subtle clues if you know where to look. Drivers often notice a change in how the Audi S5 responds, an unfamiliar sound, or a warning message on the instrument cluster. Cataloguing these symptoms is not busywork; each one narrows the list of likely causes and helps a technician zero in on the real fault instead of replacing parts on a hunch.
- Red BRAKE symbol illuminated
- Soft, spongy or sinking brake pedal
- Brake fluid low in the reservoir
- Longer stopping distances
- Sometimes lit with the handbrake released
What Causes the Brake System Warning Light to Come On?
There is rarely a single universal reason the Brake System Warning Light appears on a Audi S5; instead there is a shortlist of usual suspects. Root causes range from simple, inexpensive items to genuine component failures, which is why a proper diagnosis always beats guessing. Understanding the common triggers on the Audi S5 helps you have a more informed conversation with your mechanic and avoid paying for parts you do not need.
- Low brake fluid level
- A hydraulic fluid leak
- Worn brake pads dropping fluid level
- Faulty brake fluid level sensor
- Parking brake not fully released
How to Fix the Brake System Warning Light on a Audi S5
Fixing the Brake System Warning Light on a Audi S5 is methodical, not mysterious. Start with the quick, no-cost checks, then let the vehicle's own trouble codes guide you toward the specific system at fault. The ordered steps here are designed so that by the time you (or your technician) reach the more involved work, you have already eliminated the easy explanations.
- Confirm the parking brake is fully off
- Check the brake fluid reservoir level immediately
- If the pedal feels soft or fluid is low, do not drive — arrange recovery
- Look under the car for fluid leaks at the wheels
- Have the brake system inspected and bled by a technician
Is It Safe to Drive With the Brake System Warning Light On?
Whether it is safe to keep driving your Audi S5 with the Brake System Warning Light on comes down to urgency (critical) and behaviour. As a rule, if the light is red or flashing, or the Audi S5 is running poorly, stop somewhere safe and arrange help rather than pushing on. If the light is amber and the car drives normally, you generally have time to reach a workshop — but 'have time' is not the same as 'ignore it', so book a check promptly.
Diagnostic Trouble Codes Linked to the Brake System Warning Light
If you scan a Audi S5 showing this light, these are the OBD-II trouble codes most commonly associated with it. The code you actually retrieve is what pinpoints the repair.
| Code | Meaning |
|---|---|
C0035 |
Left Front Wheel Speed Sensor Circuit The ABS module has lost a valid signal from the left front wheel speed sensor. |
C0110 |
ABS Pump Motor Circuit Malfunction The ABS hydraulic pump motor circuit has failed, disabling anti-lock function. |
Professional Mechanic Tips
If the brake pedal on a Audi S5 goes soft or sinks to the floor with this light on, stop driving — that is a hydraulic failure, not a sensor glitch.
Frequently Asked Questions
Why is the Brake System Warning Light on in my Audi S5?
Your Audi S5 turned on the Brake System Warning Light after its self-diagnostics flagged an issue in that system. Because several different faults can trigger the same symbol, the smart first move is an OBD-II scan to pull the specific code before you spend any money.
Can I keep driving with the Brake System Warning Light on?
For a Audi S5, a steady amber Brake System Warning Light with normal driving generally allows a careful trip to a garage. A red or flashing light, or any change in performance, means you should stop and avoid further driving until the fault is identified.
How much does it cost to fix the Brake System Warning Light on a Audi S5?
There is no single price for the Brake System Warning Light on a Audi S5; it ranges from a no-cost adjustment to a component replacement. The honest way to control cost is to diagnose the exact code before authorising any repair, so you only pay to fix what is actually wrong.
Will the Brake System Warning Light reset itself on a Audi S5?
If the trigger was temporary, a Audi S5 may turn the Brake System Warning Light off automatically after a few drive cycles. If it remains lit, the vehicle is telling you the fault is still present, and the symbol will only go out for good once the cause is fixed.