Did anyone ever get a fix on this, my 09 just started this the other day. My scan gauge and a multimeter both are picking up the alternator output bouncing back and forth between 12 & 13 volt range. All the lights pulse except the HID's (the ballast probably keep those from pulsing). Have not started to isolate components yet, assuming the voltage regulator is going, but hate to spend $$$$ on alternator and still have the problem. thanks,