I have a 1990 dodge dokato and I can't get no trailer lights. will the converter go bad.

 

could be a fuse. my 02 dakota has a fuse under the hood, but if it's an aftermarket thing the fuse could be anywhere. Wires, especially ones exposed to the elements, can corrode and lose contact. Your best bet is to trace the wires and find out what's wrong.

And you might try asking in the Dakota forum instead, there are some guys who would know the older gen Daks better in there.