Depends on the make, model and year, Ace.
I find it amusing that people want help with the cars, but they don't mention make, model, year, or anything else. Throw us a frikkin' bone.
Autozone may have that wiring diagram info. Register at autozone.com, put in your year, make, model & engine size, then click on repair info, chassis wiring, wiring diagrams, or just wiring diagrams.
Once you locate and verify that the fuse is good,the little push button switch between front of door and body of car(where door hinges are located)could be bad.You might be able to go to Autozone.com and enter your vehicle info in then click on repair help.Then click specifications and a list will pop up with your choices.
The courtesy fuse on many american cars, look at the fuse panel cover or the owners manual for the fuse layout.
