trailer lights question..help

Hi, I'm a new boat owner and still learning. After I bought the boat, the trailer light is not working properly. All but the standing lights don't come on which sucks because I can't be out after dark. Some people said it could be the grounding wire, but I tried placing it on other metal parts and it still didn't work. Any advice, ideas? Thanks in advance.

Same here I bought mine and someone had cut the end off of the wire I only have 3 wires on mine but the plug I bought has four so what do we do I would like an answer to?

Any help at all? thanks

With a good battery to use for trouble shooting, connect the negative battery terminal to any portion of the trailer, then using jumper wires, connect the positive battery terminal to one of the wires leading to the lights. Without actually being there, it's just about impossible to step by step walk you thru the trouble shooting procedure.

I've encountered all kinds of problems with trailer lights... one side grounded, the other not, bad bulbs or bulb sockets, etc. A good starting point is to make sure that the bulbs are good and the sockets free of rust and corrosion. You can start right directly at the light assemblies, making sure that they work properly, then work backwards towards the trailer connector.

Check the source, your car or truck for 12 volt at plug. The lights work off the vehicle lights and turn signals and brake lights. If you have power there check and clean all light sockets contact points. Try new bulbs or clean contact on bulbs, they sometimes corode. Check for good ground. Check for broken wires. Clean contacts on both ends of plug, Male and female. If all else fail buy trailer light kit and install by instructions. For the other guy ,buy new plug and but splice
to old wiring harness , you going to need that wire hooked up for all lights to work.

I did the check for clean sockets, bulbs, use spray clean and truck lights are good. The previous owner ground the ground wire onto the trailer and said it worked for him. Thing is, I have towed my buddy's boat before and his trailer lights worked great. I wonder if the wires going through the trailer is bad somewhere?

Another questions is: would I be charged a lot of money if I take it in to a shop?

Spend the money and get the LED light kit at Harbor Freight and spend a couple hours and rewire your trailer. I think I got my kit on sale for $30 or something. There are better LED kits out there but it is going on 4 years now with mine and I don't even unplug them anymore when launching my boat since they are sealed. One key, solder all connections, cover with liquid electrical tape and shrink wrap them. That connection will most likely outlast the trailer itself, even in salt water. The kit I bought at HF had two tail lights, one of which had a white "down" light for the license plate, two yellow side marker lights and I think 30' of wires and the plug.

Thanks for the suggestions. Where is Harbor Freight? I'm from Madison, WI.