what i would do is crawl under the truck,drivers side under the cab infront of the front tank.check to see if it is rusty(maybe a bad ground).use a test light find a good clean ground and see if you have power to the wire,if yes the valve could be bad or have rust on the frame causing a bad ground.this was the problem on mine.a new valve is under $50.00 if the valve is bad.i just cleaned the frame and the mounting tab,use lots of die electric grease and tightened it up and no problems.let us know what happens.BTW welcome to the site.