I believe this product's bad reviews are from people who do not understand the different ways this relay can be used or wired. It has worked perfectly in 2 different situations I have used it in as designed. If you need a 5 terminal relay with harness and know how to wire one in correctly this is the one! Many custom modifications to interior lighting systems can use this in conjuction with switches and factory systems. I will purchase this one every time I need one!! 20+ years as GM Tech specializing in electrical repairs