found this in an old post by boomtruck97 dated/closed 04/28/2009, it was very helpful with wiring diagrams for my 1991 S10 chevy blazer, but also good for any vehicle and thought worth bring up to date.

autozone.com - there is a link on the right side of the main page called vehiclerepair guides - it is free to register and use. they have the diagrams and such in there for PDF view or download.

It refers to free wiring diagrams but also to troubleshooting your vehicles problems, best of all it is free, all you need to do is register.

here is the original link