This question was asked by another user but I have the same problem:

--I recently replaced my battery and immediately after that I had stereo problems. The LED on the stereo says there is an error and also my alarm light is blinking in the upper left-hand corner of the stereo. I'm not sure if changing the battery caused problems with the stereo or alarm system. It seems all it needs is a reset code or set of instructions but the manual didn't mention anything. Stereo and alarm are from the dealer (stock).