One problem related to speed sensor has been reported for the 2012 Hyundai Sonata Hybrid. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Hyundai Sonata Hybrid based on all problems reported for the 2012 Sonata Hybrid.
See submission number 10559603 sent prior to this on 1/14/2014: this is a continuation of the explanation of the cruise control/transmission/power train issue experienced with the vehicle since new. The text from that submission continues to its end. "it would appear that the cruise control/power train computer program has some errors in it or needs updating to correct the problem of excessive acceleration when re-attaining a set speed from a coast down that causes the car to go below the set speed before the sensors detect and activate the acceleration required to bring the car back up to the set speed. Then is 'shoots' the car forward at full power-like unintended acceleration might- and send it up to as much as 10 mph above the 'then set' speed I have desired. If there is a corner at the end of the rise, the car can feel out of control during this acceleration as it is at full power during the acceleration phase. The transmission also down shifts 2 or 3 gears during this process which aggravates the fierce acceleration feeling. These incidents have been reported both to the Hyundai dealer and to Hyundai. Hyundai says, take it to our dealer; the dealer says they can find nothing wrong as no dash warning lights are ever showing and their electronic scanning brings up nothing of any kind of problem. This may or may not be exclusive to the Sonata Hybrid with cruise control and since many people do not use cruise control on winding rural roads, they may not/never experience the same sensation that can happen often to me. I can deal with it. Nhtsa should keep this report on file in case other cruise control or acceleration issues with Hyundai vehicles surface as my report is precisely defined as to what type of road condition it occurs on and what happens. Thank you.