I have a 2006 convertible touring, out of the blue the key fobs stopped working to unlock the car and the security light on the dash stays lit. It had a blown fuse under the hood I thought replacing that would fix the issue but no luck. The car does have an after market remote start would that cause this problem? Any help would be greatly appreciated

 

Yes, the aftermarket remote could have something to do with it because the remote start needs to be able to bypass the security system to be able to start the car without the key being present. Remote start technology is very well guarded for obvious reasons, so you're not going to find a simple fix on the internet. You could try disconnecting the battery, shorting the positive cable to the negative cable (NOT shorting the battery!) to drain any residual voltage in the car and see if that resets the computer. If that doesn't do it, you may have to take it back to the shop that installed the remote starter.