A buddy of mine hooked up an aftermarket stereo in his 2013 Silverado. Now his turn signals blink weird. They blink 2-3 times like normal then blink really fast. Yes, he does have led blinkers so the fast blinking is normal. The 2-3 normal blinks at first are throwing us off. This just started after the stereo install. Any ideas.?

 

sounds like a wiring issue. i dont know where the problem lies - but rechecking the wiring and grounds and all of those related issues would be a good start.