Brake Master Cylinder Problems of Hyundai Kona

The brakes began feeling less effective the day before because the car crept forward at a light but the driver thought they may have just eased off the brake pedal. The next day during a 45-minute drive to work the brakes felt more ineffective and a dash display warned "low brake fluid". The parking brake light was not on while driving. Drove the car from work to the local Hyundai dealer in alexandria, va a mile away. The dealer refused to look at car at all and said to come back in 18 days. The dealer said no loaner cars were available. Drove the car back to work. On the way home the parking brake light came on. Got home and saw the owners manual says to park the car and not drive it when the parking brake light comes on while the parking brake is released. Checked the brake reservoir and it was completely empty. The brake pedal went to floor and the only way to stop the car was to use the parking brake. The reservoir was refilled but all fluid was gone in a few hours of driving. The car was towed ten days later to the same dealer after a manager at the dealership got involved. The tow truck driver had to use the parking brake to drive the car out of the parking garage. The dealer advised the problem was a faulty caliper. The owners manual claims the car has a "dual diagonal" braking system as required by law but somehow a single leaking caliper resulted in a complete loss of pedal braking and all brake fluid from the master cylinder reservoir in a short period of time. Had this happened on a highway instead of city streets this could have been a fatal. The brake master cylinder reservoir does not seem to be a "split" reservoir. It has a separator but the "wall" does not go all the way to the top of the reservoir. I believe that when the brakes were used the fluid splashed from the "good" half to the leaking half because the reservoir is not 100% physically separate for the two sets of brakes.

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