Cruise Control problems of the 2012 Hyundai Sonata

Brake light switch plunger does not retract as it should when the brake pedal is not being pressed, car looses acceleration and looses power. When driving on cruise control, break will depress and turn cruise off and on in dash.

While driving at any speed with the gas pedal depressed, the car will suddenly slow down when I hit a pothole or bump in the road. It does the same thing when using cruise control. For example, I'll be driving 50mph and I'll hit a bump in the road and my rpm and speed will drop. If I take my foot off of the gas then re press it, it re engages and accelerates again.

When attempting to initiate cruise control on the highway only the on/off button will work, show with the illumination of the cruise light on the dash console. The set and resume buttons will only work approximately 30% of the time and the cancel button never works. When the system is allowing me to set it the only way to disengage it is via the brake.

When the headlights are in use, the car randomly loses power, headlights turn off, entire car just shuts down without warning, then after several seconds, powers back on. The lights, engine, everything turns off. Also, when headlights are in use, cruise control and stability do not work. The vehicle is in motion and this has happened on highways and city streets. I have taken my vehicle to the two nearest dealers and they refused to fix the vehicle. Generally, this happens when braking, using turn signals, changing to hi beam/low beam, but has also happened for no reason at all.

Cruise control will not set, accel, or cancel intermittently with daily use of the car. It works usually when you first start driving the car but not always. The cancel button rarely works at all and there have been instances when the only way I could cancel cruise control was by hitting the brake pedal. Several near collisions because of the failure of the switches on the steering wheel working. I've taken it to the dealer repeatedly to have it repaired and they say they can't duplicate the problem. I bought the car new and just recently had it at the dealership again and now they say they won't cover it under warranty and that it would be customer pay. Hyundai has a database showing when I've had it in to be looked at. Today's visit was at roseville Hyundai in roseville, CA (916) 677-3636 service advisor 7713 calden, christopher. October 17, 2015 work order 146002.

On Jan 26 my husband was driving home and the road conditions were slippery. When he went to apply the brakes, he heard a loud pop and the brake went all the way down to the floor and would not come back up. Luckily this happened around the corner, but by the time the car made it into the driveway the brakes were smoking. I had to have the car towed to the mechanic. We had to replace the front brake pads, calipers and rotors. Also the brake switch oem had to replaced. When all said and done the total cost came to 729. 64. Can I tell you how disappointed I am in this vehicle?? this vehicle is only a 2012 my high beams don't work nor does the cruise control. I am starting to think this car is a real lemon!!! at this point I would like to know if the brake system has any recalls because my bill was extreme and should not have happened on a 2012. I do not have the VIN number on me at this time. Very very disappointed and have nothing good to say about this car!.

The contact owns a 2012 Hyundai Sonata. The contact stated while driving 55 mph with the cruise control activated, the cancel cruise control button was pressed but the vehicle failed to stop. The contact had to apply the brakes in order to disengage the cruise control. The problem recurred several times. The vehicle was taken to a dealer. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 22,425. . . Updated 10/21/14.

I took my car into the Hyundai dealer for a 30,000 service. They said the computer has an upgrade to the software. After the upgrade, the cruise control speeds up by 4 - 5 miles per hour when it is set. For instance, if you set it at 65 mph, it will speed up to 69 or 70 mph and then slow back down to 65. It does this when you initially set the speed or if you brake and then hit the "resume" button. In the case of "resume", if you initially set it at 65 mph and use the brake to slow down and then use the "resume" button, the car will speed up to 69 or 70 before going back down to 65. The cruise control will do this no matter what speed you initial set it at. I took the car back in and the service people thought it was strange. So they said they ran the upgrade to the software again, but it has the same issue. They then told me that the surge in speed was within an acceptable tolerance range. I have owned many cars with cruise control and none of them have ever done that and this car did not do it prior to the software upgrade. It is pretty dangerous if you are not paying attention.

On 09/22/13, I left for a 75 mile trip. When I first started my car that morning, I noticed it was moving sluggishly, but thought it was due to our overnight chilly temperatures. I drove the short distance to the interstate. As I attempted to merge onto the interstate, I had the most frightening experience of my life. I pressed on the accelerator to prepare to merge and discovered that I had practically no acceleration! my car got to between 5000 and 6000 rpms before it shifted out of first gear! at that point, I was going approximately 45 mph while trying to merge onto an interstate, in front of a semi that would not get over for me to merge. I literally had my accelerator pedal pushed to the floor, as the car again hit between 5000 and 6000 rpms to shift into second gear! I was able to eventually get my car to 65 and turn on the cruise control . I double checked to make sure I was in drive (rather than neutral or manual--no dashboard lights on). On occasion during that drive, I turned off the cruise and hit the accelerator to see if what I had experienced was a fluke¿it was not. My accelerator was literally mashed to the floor as my car¿s speed slowly lurched higher, while my rpms raised above 5000 before shifting to the next gear. Once I returned home, I turned off my car for a few minutes, before restarting the vehicle to test it. The transmission problem was gone (although I question whether my turbo is still working effectively, as it seems less responsive). Today, I took my car to the local car dealership to address the recent Sonata recall, and I also requested they examine my transmission, describing the above incident to them. I noted that other drivers mentioned that a ¿waste gate� issue appeared to be causing the shifting problems. They could find no problems and suggested I shifted into manual accidentally.

Car in park, key in ignition-motoridling--wife and I awaiting to board ferry car suddenly reved very high with tach over 5--checked car was in park no obstruction (mat etc. . ) or foot touching gas pedal--killed ignition to stop uncontriled reving of engine. Four witnesses ti incident--two in car, two standing next to vehicle. Called dealer immed and made apointment to have car checked---first uncontroled incident on cruise control April of 2013, second sudden increase August 5th 2013 again on cruise control--dealer found brake switch problem after 8-05-13 sudden surge but claims "can"t replicate additional surges. . Cruise control used on way to ferry. Car taken to dealer 8-26-13 again they can't replicate. Occurs when in cruise control more than 20-30 min. Or more--perhaps wiring or modules heating up--dealer no help!!!!!!.

Cruise control would not disengage by hitting cancel or turning it off. It would only disengage by depressing brake pedal. I have been having problems engaging cruise control for about a week. The brake interlock switch was already replaced once, if it had failed again the only option would have been to put the car in neutral and shut it off.

The cruise control fails to engage every time you press it. Sometimes it works, sometimes it doesn't. Dealer replaced the switch saying it was bad. Problem persisted so I took it back in. They cannot replicate it since it is intermittent therefore I cannot get this fixed.

Westbound on I-78 near harrisburg, PA while traveling on cruise control vehicle motor increased without driver input from 65mph to over 72mph to the point of 80mph before several hard foot pressures on brake disengaged cruise control. Car did not respond to normal brake pedal tap to disengage. Called dealer who suggested we not use cruise control and on return had them service--dealer could not replicate and returned car. On 8-05-13 which was next highway trip on 440w in staten island, NY while on cruise control at 60mph (flow of traffic) car suddenly made high reving motor noise, lurched forward and increased speed to 0ver 70mph--brake again did mot disengage car but heavy (very heavy) pressing on disengage button slowed car. Car to be looked at after our return--scheduled check 8-13-13.

I was driving down a hill that was not very steep, in good weather, with cruise control on at 60 mph. As the car went down the hill, the speed increased to 80,at which point in time I used my brake to slow down. The same thing has happened on numerous occasions with me alone and with others in the car, including a staff member of the dealership, who told me that this was normal behavior for a Hyundai Sonata and for the cruise control on his own vehicle. If I cancel cruise control in the middle of a hill, speed decreases or holds steady --it does not accelerate.

The vehicle's cruise control failed to engage or disengage when used. The dealership was initially unable to replicate the problem, then replaced a headlamp switch. After this, the radio began turning completely off while driving, and the cruise control continued to act erratically. The dealership said they could not replicate the problem but replaced the radio. Several more times, the dealership stated they were unable to replicate the problem with the cruise control and radio. After contacting the manufacturer, the dealership looked at the car again and found loose pins in the connector to the fuse box.

Three problems cropped up immediately or shortly after initial ownership. The car pulls to the right, and the steering wheel must be turned to the left of center to compensate when driving on a flat surface. Second, the sunroof area developed a loud creaking sound when the car is driven through a turn or over uneven road surface. Third, and most alarmingly, the cruise control intermittently fails to disengage when the cancel button is pressed. It also intermittently fails to engage when the set button is pressed. If the cruise control has failed to disengage, tapping the brake or pressing the main on/off button will cause it to disengage. However, the confusion that comes from the cancel button failure may lead to an accident. The dealer cannot replicate the problem during a short test drive and refuses to replace or test the electronic modules.