Brake Failure

[LAD]

I just had my brakes fail today on my 2013 Hyundai Genesis Coupe 3.8L.
I was stopped at a red light in the left turn lane. All of a sudden I was rolling forward while my food was firm on the brake. I was able to press the brake even further, but I kept rolling forward until I crashed into the car in front of me. Thankfully, it was a very sturdy truck with a trailer hitch. I have damage to my grill where the hitch hit my car. The brake pressed to the floor and did not stop my car from rolling forward. I was able to drive the car to the closest parking lot in that intersection. I waited for a tow to the dealership. The brakes seemed to work fine again; the service department told me there was nothing wrong with my car or its brakes. I left the car with the mechanic to drive home and continue to test it to reinact the problem. When I googled "hyundai genesis brake failure", there were a few other instances of this issue. I am so scared to drive my car again.

 

[TLIN]

Next time if happens again maybe try putting the gear selector in neutral and hit the e brake.
Also did you try pumping the brake pedal? How many miles do you have on your Genesis?

 

[Southern Boy]

When I had the brake fluid changed out on my Genesis I asked my Technician if the TB Hyundai issued was due to the reported brake failure / fading reported.
He said no that Hyundai just decided that DOT 4 synthetic was the correct brake fluid for these vehicles.

He went on to explain that the intermittent failures and fading brake problems was traced back to the ABS units. It seems that some of these ABS units had air bubbles internally and no matter how many times they were bled all of the air bubbles couldn’t be removed, so the policy was just to replace them when there was complaints of intermittent brake failure / fading.

This could be your problem. There are threads on this site detailing these braking problems, but what my technician told me about the ABS unit problem was the first time I heard this explanation

 

[Mark_888]

He went on to explain that the intermittent failures and fading brake problems was traced back to the ABS units. It seems that some of these ABS units had air bubbles internally and no matter how many times they were bled all of the air bubbles couldn’t be removed, so the policy was just to replace them when there was complaints of intermittent brake failure / fading.

I am sure that is what your dealer told you, but I am not sure I believe it. Some of those who had their ABS units replaced said their dealer showed them were it was leaking, not that they had air bubbles.

 

[Southern Boy]

I am sure that is what your dealer told you, but I am not sure I believe it. Some of those who had their ABS units replaced said their dealer showed them were it was leaking, not that they had air bubbles.

I'm sure that a leaking ABS unit would cause brake problems, but if there isn't an obvious reason for fading and intermittent failures then I would inquire about the Air bubble problem with some of these units.

 

[Gunkk]

LAD - file a report here: https://www-odi.nhtsa.dot.gov/ivoq/ you may help save someone else's life.

I'm one that had my ABS module replaced for brake failure. Not as extreme in the OP and no crash involved, but I did have a pedal-to-the-floor experience near miss (was going < 40 mpg and was able to get brakes back before I hit the car in front of me). After that first time, it followed with slow "leak" type behavior. Tech didn't immediately "feel" it at idle while sitting in the repair bay at the dealer, but confirmed it after the first test drive and they replaced the ABS module under warranty.

This is the first time I've heard of the "bubbles" failure mode, but given that dealers are doing LOTS of Dot3->4 fluid replacements these days, it doesn't surprise me that some techs are having difficulties. The fluid replacement/bleed procedure is quite involved!

TLIN - not sure if the 2013 electric ebrake can be activated while in Neutral. Might have to slam it in park or reverse. 2009 was a mechanical pedal/cable setup.

 

[margratemary]

The brake fluid went somewhere, it’s either on the driver’s side floor, which indicates a master cylinder leak, or there is a puddle by one or more wheels where it’s leaked out. And for all I know it could be some problem in the brake power booster