Checking the Low Brake Fluid Warning Light (Mercedes-Benz S-Class W126)

The brake fluid reservoir (2) is located in the engine compartment. Its cover (4) has a ventilation hole, which must not be blocked under any circumstances. The reservoir has transparent walls, so that the brake fluid level can be visually checked at any time. When the reservoir cover is closed, the level should not go above the "max" mark or below the "min" mark.

Only DOT 4 compliant brake fluid should be used.



Wear of brake pads leads to a slight decrease in the brake fluid level, which is normal.

A sharp and rapid drop in the brake fluid level indicates a leak.

The leak must be localized immediately. It is usually caused by worn seals in the wheel brake cylinders. The system should be checked in a workshop.

Checking the indicator lamp

Turn on the ignition, turn off the handbrake.



Press the contact from top to bottom.

The assistant should check whether the lamp lights up. If it does not, check the wiring according to the wiring diagram.

The contact inserts are non-removable. If necessary, the tank will have to be replaced.