I have a Black 2002 Dodge Ram Sport 1500 Quad Cab 4.7 4x4 (112k miles) and have a electrical issue at hand. I'm not an electrical guy.
I did notice I didn't have a ground wire from cab to bed. So, I went to autozone bought a ground cable and put it on and still nothing. I had a dealer do some body work recently, which they had to take the bed off and apparently never put this cable back on that they cutoff without my knowledge.
My issue is that I do not have any day time running lights in front or rear. I also don't know if it has any connection, but I noticed my adjustable brake pedal, license plate lights, backup lights, and 3rd brake light are not working. I did replace the 3rd brake light, backup lights and license plate lights, so unsure why they still don't work. Everything else works fine; brake lights, head lights, fog lights, dash lights, and all interior lights. Nothing else is acting strangely.
I have checked all fuses and found none blown and checked all relays by swapping them out with other known working ones and all is good there. I have checked all wire connections to ensure they were plugged up tightly and moved wires around while lights were on to see if they would start working even around the hitch encase the dealer's body shop messed those up. Still nothing. I also checked all ground wires that I could locate.
I have replaced the brake light circuit boards (both and one of the sockets had a slight burn to it), head light switch, and every bulb (including head lights) that I could think of even if they were good, which all were.