Why doesn't my stereo control work on stereo

I’m sorry to hear that your stereo controls on your steering wheel are not working. I found a thread on the Suzuki Forums where a user had a similar issue with their 2011 Grand Vitara¹. One of the suggestions was to check the settings on the radio itself and reset it if necessary. Another suggestion was to check the wiring diagram for the controls and see if there is a fuse that needs to be replaced. If you are unable to resolve the issue, it might be best to take your car to a professional mechanic who can diagnose and fix the problem.

I hope this helps!