Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Broken

I used it only for 2hours or so while driving and after a while, the green light was gone. No matter what I did, the power indicater was not turned on. I am not sure if it was broken while driving and it was too late to returned this product. Sorry it is only one star. If it was working fine, I would have given 4 stars.