Had maintenance service at dealership after 2 week...

Had maintenance service at dealership after 2 weeks engine shine appears on my dashboard went to check what s the problem they told me they have to diagnose the problem.For 10 minuets of diagnose/labour I paid $160. After that I went to another dealership they did diagnose and charge me for parts n labour only which I save almost half of the price they were asking for.not happy at all definitely not going to get any of my service done.its not about the money it s about trust to those people who don t have much experience on vehicles maintenance.sad part is we just have to trust them whatever they says....