Attention! Brake fluid is an aggressive component for the skin, especially for the eyes, is acutely toxic when it enters the body and destroys the paintwork. It is extremely hygroscopic, absorbs moisture from the environment, which leads to the loss of its functional properties.
Use only DOT4 fluid.
Mixing different types of fluids such as DOT3 or DOT4 with DOT5 may cause brake system failure.
There is one reservoir for brake fluid and clutch fluid, located in the engine compartment under the cabin air microfilter box on the left side (driver's side). The threaded plug has a ventilation hole, which must be kept clean (open) at all times. The tank is transparent (Fig. 2.23), which allows you to monitor the liquid level in it.
A decrease in the level below the "MIN" mark (2) is signaled to the driver by the indicator on the instrument panel lighting up and the appearance of a message "Check Brake Fluid".
To visually check the brake fluid level of the BMW X5 E53, remove the microfilter box from the driver's side. The fluid level with the plug closed should be between the "MIN" (2) and "MAX" (1) marks and not go over them.
Due to wear of the brake pads, a slight decrease in the brake fluid level is possible. A significant decrease in the brake fluid level indicates a leak from the system. It is necessary to stop using the car and immediately identify the location of the fluid leak.
In the process of visually monitoring the liquid level in the tank, it is necessary to check the functioning of the contacts of the float level control mechanism.
Check the operation of the control indicator in the following order:
- set the ignition key to position "1";
- release the parking brake lever:
- press the button in the tank cap with your finger;
- track the indicator light on the instrument panel (a second person or a mirror mounted on the back of the seat is needed). If the lamp does not light, check the electrical circuits.
- Install the air conditioner microfilter box in place. Drained (spilled) brake fluid must be disposed of.