Because brake fluid is colorless, it may be hard to know if it leaks simply by checking underneath your car. Some signs that your brake fluid is leaking include:nCheck for fluid: If you know what to look for, a puddle of brake fluid can be found between the front of the car and the wheels if it leaks, which is where brake lines are located.nWheel wells: Check for an oily substance on the car’s rocker panels or wheel wells.nLoss of pressure: When the brake fluid leaks, air can get into the system, which means a pressure loss. The brake pedal will then feel spongy and soft.