2006 to 2013 S-Class Mercedes-Benz Check or Add Brake Fluid
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Is the brake fluid warning light displayed on your Mercedes-Benz? Learn how to fix the problem by adding brake fluid to your Mercedes-Benz S-Class. This guide is a step-by-step procedure to check and add brake fluid on a 2006 to 2013 Mercedes-Benz S550 W221.
At a Glance
- Fits: 2006 to 2013 Mercedes S Class W221.
- Fluid: new DOT 4 from a sealed container.
- The reservoir is on the driver’s side near the firewall; keep the level between MIN and MAX.
- A slowly falling level usually means worn pads; check them before topping up.
- A fast drop or soft pedal means a leak; don’t drive it.
What you will need
- Brake Fluid (DOT 4+)
Procedure
- Pull the hood release under the dashboard. Locate the hood latch on the vehicle’s front and slide it to the right to unlock it. Open the engine hood and hook it to the engine hood stand.
- Pull the hood up until the hood struts are in hold position.
3. Locate the brake fluid reservoir on the driver side of the engine compartment near the firewall.
4. Check the fluid level on the reservoir; there’s a minimum and maximum label. Use a light behind the reservoir to see the fluid level more easily. It is important to check the brake fluid level to prevent air bubbles from the brake lines and poor braking performance. Bleeding the brakes also eliminates air bubbles.
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5. If the brake fluid is at the minimum level, open the cap counterclockwise.
6. Pour in the Brake Fluid (DOT 4+). Make sure that the brake fluid is from a sealed and unopened container, fill only to between MIN and MAX, and wipe up any spills right away because brake fluid damages paint.
7. Close the cap by turning it clockwise. After the top-up of brake fluid, observe if it reaches the minimum level again in the brake fluid reservoir. If this occurs, there could be a possible brake leak. Inspect the brake lines and hoses’ condition, inspect the condition of the brake caliper seal kit, and replace the old ones if needed.
Why the level drops
The level falls slowly as the brake pads wear, because the caliper pistons move out and hold more fluid. A level near MIN on a car with worn pads is normal and will rise again when new pads are fitted, so check the pads before topping up to MAX.
A level that drops quickly, a soft or sinking pedal, or wet spots near a wheel mean a leak. Do not drive the car until it is inspected.
Check these troubleshooting and repair guides for more help on your Mercedes-Benz.
