Complete brake failure on two occasions

axplayer said:

It looks like one other person here reported a similar problem, but I have what seems to be a pretty serious brake issue. I have a 2009 Genesis Sedan (4.6). It has about 20K miles. On two occasions now, both about 3 months apart, I have had total brake failure at low speed, after slowing down from highway speed. Once was as I turned into a parking lot off a highway. The other was turning into my neighborhood of the highway. I was thus rolling along at fairly low speed at the point the brakes failed, but the only way to stop was to apply the emergency brake. The brake pedal pushed all the way to the floor with almost no resistance. On the first occasion I had braked a bit hard before the failure, so I thought perhaps it was an overheating issue. The second incident was not preceded by hard barking. Needless to say, this is a little disconcerting and, of course, a problem that the dealer will likely not find--although I fully intend to take the car there. I'm just trying to get a sense of whether this has happened to anyone else. Any takers? Thanks.

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ALMOST EXACT SAME PROBLEM. Was entering the freeway on a downhill grade onramp. Car in front of me was at red traffic control light. I pressed brakes...absolutely nothing...floored brake pedal to the floor...still nothing. I braced for impact as my tin can rear ended a superdutyt toyota tundra. Completely ripped off the front end on the drivers side back to the drivers door. Impact spun rear right of car to the right into a construction concrete wall....broke the rear right mag in half.

HOW MANY OTHERS ARE HAVING BRAKE PROBLEMS?

I'm feeling pretty screwed here...2010 Genesis 2 dr 4/Turbo. JUST turned 14K miles so it's virtualy brand new. Seriously, WTF???

I know Hyundai battled with proissues concerning their brakes and steering lines in the past, but I was so certin they'd overcome all their earlier problems; this car just seemed to drive like a dream...only it's now turned into a horrible nightmare.

anyone know of any other owners' foruns where I can find other Genesis owners who might have experienced the same total btake faiure as I have

ewebnation said:

anyone know of any other owners' foruns where I can find other Genesis owners who might have experienced the same total btake faiure as I have

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You need to find a reputable lawyer ASAP.

Please, please, please go to https://www-odi.nhtsa.dot.gov/ivoq/ and file a report.

Question for the experts:
Slight rubbing for extended periods at highway speed could potentially cause extreme brake fade (vaporized brake fluid), correct?

Gunkk said:

Question for the experts:
Slight rubbing for extended periods at highway speed could potentially cause extreme brake fade (vaporized brake fluid), correct?

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Unlikely with good, uncontaminated brake fluid. Quite possible with low quality brake fluid or if water has gotten past the caliper seals and into the brake fluid.

It is normal for disk brake pads to be in contact with the rotors - there is no spring to pull them back when you release the brake pedal. The pads push back against the calipers until they're basically no longer compressed at all and will still be in slight contact with the rotors. If a problem exists that keeps the pads in firmer contact with the rotors (e.g. improperly adjusted pedal to master cyl clearances so fluid can't be pushed back into the reservoirs, rust/gunk adding excessive friction to the calipers) then the pads will wear on the rotors. This makes excessive heat which can, depending on severity:
1: lead to an overheated rotor and/or warping the rotor. If you see blue streaks on the rotor it's garbage - it's been really overheated.

2: pads will wear rapidly of course.

3: overheated pads can glaze - getting a hard surface. They'll start making squeak noises when used. Also, high temps in brake pads (especially simple organic pads as well as cheap pads) will boil off some of the adhesive which forms a thin vapor barrier between the pad & rotor... this acts like oil... making the brakes ineffective. This is the most common form of brake fade on cars. (edit: drilled or slotted rotors, like you see on performance cars, help this situation: the holes/slots give the vapor some place to go so the pads can still do their jobs)

4: really hot calipers will eventually cook the brake fluid, causing it to boil. New/fresh fluid has a fairly high boiling temp but, as brake fluid ages (and absorbs humidity which it LOVES to do) the boiling temp reduces. Once the fluid boils it won't transfer pressure from the pedal/master cylinder to the calipers so the brakes are useless again.

Simple tests for dragging brakes:
1: jack the car up, put it on jack stands, parking brake OFF, transmission in neutral. Spin each wheel. Compare a wheel to its twin on the other side of the vehicle: how easy is it to spin, how long will it coast. On rear drive Genesis cars, the rear wheels will be a little harder to turn than the fronts. For most other cars (front drivers) the front wheels will be tougher to turn. Any wheel that spins harder, or won't coast much, compared to its twin on the other side has brake issues. Any wheel that makes different noises has issues too.

2: easier test: go for a drive on an empty road at moderate speeds. Drive for a few miles. COAST to a stop, put the transmission in Park. Basically, the idea is to NOT use the brakes for 5 to 10 minutes. Hop out of the car and put your hand NEAR TO BUT NOT TOUCHING the rims (or use one of those infrared heat sensing guns) - feel the heat being radiated from the brake area. Compare a wheel to its twin on the other side again. Heat = brakes dragging. If you have to use the brakes a few times before you can get to that empty road you'll have to either a) drive on that empty road a long time to cool the brakes or b) pull over and let the brakes cool before starting the 5 - 10 minute test drive. Ideally you start with fairly cold brakes.

mike c.

Update on my situation: The third time the brakes failed and the pedal went to the floor, I captured it on video and took it straight to the dealership. They determined it was a faulty master cylinder and replaced it. This after they replaced various other parts, including, and this is from my invoice, a switch assembly, the "mechatronic" (costs about 4K), and a guide sleeve. All were warrantied.

All has been well for 8 months until today when, guess what, the brakes failed again. Now by "fail" I mean had I really needed to stop in a hurry, I would have slammed in to whatever was in front of me. But by pushing with all my might, not driving fast to begin with, and pumping some, the car rolled to a stop. Now of course the brakes are working fine again. After it sat in a parking lot for a bit with the engine off, the brakes returned to normal.

Brake fluid levels are fine, there no signs of leaks, etc. I know my way around cars and this one's a mystery! The problem is random, intermittent, and tough to duplicate at the dealership. I either need to get rid of this car or capture the problem again on video and possibly see if the dealership can "fix" it for the third time, although I have no faith left that they can.

I filed an NTSB complaint. I'll get in touch with Hyundai tomorrow. I'm seriously at a loss here and ready to get rid of this car unless something is figured out. Thanks for listening, and I'd welcome any additional thoughts people have.

Well, now I see some others have reported this problem. And like many others, when things work fine, we don't always troll these sites. I wish I had followed it closer. My dealer has never mentioned the ABS assembly. I am hesitant to take it back there unless they will commit to maybe trying that. Would it be worth my while to talk with Hyundai Consumer Affairs and maybe put them in touch with the dealership? The back and forth to the dealership is a real whip. Thanks.

Sorry, meant NHTSA, not NTSB.

axplayer, this is completely unacceptable. A car where the brakes randomly fail is undriveable. I at this point would be pushing for a lemon law buyback, so get it on camera and take it back to the dealer once again. Please PLEASE make sure you document your trips to the dealer.

axplayer said:

The dealership ruled out anything mechanical and decided to replace some ABS-related part. Apparently it costs a small fortune, so I'm glad it's under warranty. In the meantime, I've been living on the edge, driving the car until that part arrives. No problems so far. Thanks for the all the suggestions.

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Same problem as in This thread "Sporadic Low Brake Pedal Issue"

Yep, just saw that. Thanks. Complaint filed with NHTSA. Hyundai Consumer Affairs notified. Off to the dealership it goes.....again. Also seeking some lemon law legal advice, although Texas generally doesn't cover under its law vehicles that were bought used, as mine was.

This has happened to me. It happens when I brake hard and then try to brake again. I took it to the dealer three times and each time I told them to slam on the brakes to test them thoroughly. Each time they said they fixed it. Each time I ended up driving thinking it was fixed and when an emergency brake situation came up the brakes would work then be useless afterwards. Finally on the 4th time I had them replace the master brake cylinder and now it "seems" fixed. I have a lot of miles on my car and have had this covered by my extended warranty. Each time was a $100.00 deductible. This was dangerous and could have killed me or my family. I had the vehicle towed as the brakes felt about 80-85% gone. Feel free to reply or message me for details.

jonsocal said:

This has happened to me. It happens when I brake hard and then try to brake again. I took it to the dealer three times and each time I told them to slam on the brakes to test them thoroughly. Each time they said they fixed it. Each time I ended up driving thinking it was fixed and when an emergency brake situation came up the brakes would work then be useless afterwards. Finally on the 4th time I had them replace the master brake cylinder and now it "seems" fixed. I have a lot of miles on my car and have had this covered by my extended warranty. Each time was a $100.00 deductible. This was dangerous and could have killed me or my family. I had the vehicle towed as the brakes felt about 80-85% gone. Feel free to reply or message me for details.

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How many miles are on you car? I'm curious since mine has 81k.

This could be comparing grapes to grapefruit, but motorhomes can run into this. It is often caused by water getting into the brake fluid------particularly at the caliper. You'll have brakes at first, but all of a sudden they go away. That happens when the water turns to steam and becomes compressible.

Changing the master cylinder would likely solve the problem as that would normally require a good bleeding of the brake system.

It is recommended on motorhomes to change the brake fluid every couple of years. Anyone that has his brakes quit shortly after a hard stop, should change the brake fluid out. Ford has some of the best brake fluid out there (very high boiling point).

homeofstone said:

How many miles are on you car? I'm curious since mine has 81k.

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Probably depends to some degree on whether highway or city miles, since brake usage differs significantly.

Update on my situation: Dealership replaced the ABS module (note it was the 4th time I went in for the "repair") and I drove right next door to the used dealership where we bought the car in 2010 and sold it back to them. No more Genesis for me. I suggest that anyone who has this problem report it to Hyundai of North America and the NHTSA. I had no faith left in the car, so bye-bye it went. I will not drive a car with random, intermittent brake issues. So long, Genesis forum! Appreciate the advice.

axplayer said:

Update on my situation: Dealership replaced the ABS module (note it was the 4th time I went in for the "repair") and I drove right next door to the used dealership where we bought the car in 2010 and sold it back to them. No more Genesis for me. I suggest that anyone who has this problem report it to Hyundai of North America and the NHTSA. I had no faith left in the car, so bye-bye it went. I will not drive a car with random, intermittent brake issues. So long, Genesis forum! Appreciate the advice.

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Thanks for the update,

sorry for the problems. Brakes on the cars are VERY important (as you know) ... failure is not a option. i'm guessing you got screwed on the buy back ? what did you get to replace it ?

ppp

Only got modestly screwed. Market value in my area for a similar one was 22K-something. They gave me 20.3K. Worth it IMO for not having it on my conscience that someone could experience the same problems as me.