One problem related to air bag on-off switch has been reported for the 2011 Hyundai Elantra. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2011 Hyundai Elantra based on all problems reported for the 2011 Elantra.
The airbag light switched on shortly after the warranty expired. After discussion with the dealership, they said the clock spring needed to be replaced, which costs around $300. If this is not replaced, the airbags will not deploy in the case of a collision. Based on my own research on the internet, this seems to be a common problem amongst Hyundai Elantra with recently expired warranties. Since this is a common problem, I believe this is a safety system defect and should be fixed for free under recall.