The brake light on the dash comes on and off while driving, the reason for this is that the brake fluid is slightly low. Possible Cause of Brake Light on Dash that comes on and off Brake Fluid is Slightly Low Usually, if the brake light on the dash comes on and off while driving it indicates a slightly low level of brake fluid. The top of the brake fluid reservoir is a sensor that triggers the brake warning lights to go on every time the brake fluid is low or even when the fluid is slightly low. Because the brake warning light only flashed and will not come on steadily then the brake fluid is just slightly low. Usually, the brake light flashes only when the car drove over a dip or bump, this causes the brake fluid to slosh inside the reservoir and will not be in contact with the sensor, if the sensor did not sense contact with the brake fluid then the warning light will come on. Carefully add enough amount of brake fluid on the reservoir, you can buy high-quality bra...