Do we need to change the brake fluid even if the car is parked and not driven?

Need to be replaced. Humid conditions, changing temperatures can cause brake fluid to deteriorate.

When the vehicle is parked, the air will enter the liquid storage pot through the vent hole on the brake fluid storage pot, and the moisture in the air will be absorbed by the brake fluid, and the water content in the brake fluid will continue to increase.

For brake fluid, water is one of the main factors for the deterioration of brake fluid. As the water content of the brake fluid increases, the boiling point will decrease accordingly. If the ambient temperature rises, driving for a long time or frequent braking, the temperature of the brake system will continue to rise, and the water will evaporate and gasify to form bubbles. These bubbles will hinder or block the transmission of hydraulic pressure, affect the braking effect, and even cause the brake to fail.

Therefore, whether the vehicle is in use or not, it is recommended to change the brake fluid regularly.