license plate lights wont work on 1995 Ford Explorer

ive replaced the bulbs but nothing worked. i read online that it may be a bad ground connection between the socket and bulb so im gonna clean it and coat with some vaseline. if that doesnt work any suggestions?

Asked by for the 1995 Ford Explorer
1 answer
Best thing to do is to get a hold of the electrical diagrams and start testing.
here is a good source for those: