We purchased a 2002 Dodge 1500 4x4 4wd truck. The radio and the front right blinker were NOT working. Dealership said to bring bak next day. The put in a new radio only to find it would not work. Also the light under the hood and the lighter were not working. We checked fuse box to discover circuit breaker fuse was not getting a full charge. Dealership did nothing. Now the front blinkers are going off and on. We had a friend look at the problem. He suggested it could be a module. If so, is this expensive.

If 1 signal went out, fuse is good. 2 things come to mind, Bad bulb, just cooincidence, or installer cut or used wrong wire(s). Signals go through "signalhead", in steering column.
Do the front blinkers blink at steady rate? Pull Turn signal fuse, then pull hazzard fuse.
If pulling Hazzard fuse stops front blinkers blinking while key off, With signal switch in the 3positions. Problem may be at signalhead. I see more bad installers and could believe maybe a screwup.
I could be wrong. Could have weak fuse holder.
Don't know what module he is talking about?