Towing Issues: Electrical problems while towing tent-trailer, rv service center, digital volt meter

Question
Hello  Hope you can help me.I have a Honda Odyssey 2003 and I'm towing a Coleman Cheyenne Tent-Trailer. When we were about to leave we noticed that once hooked up the lights on the trailer didn't work Diddo for the electric brakes. One of the fuse under the hood was burnt out so we changed it. Now everything seems to go crazy. With the vehicule stopped the van lights on, the trailer lights are off but if I turn them off the trailer lights go on but they are ot very bright. Throughout all that the brakes on the trailer don't work nor does the 4 way flashers. Then we take the road and then the trailer lights do the opposite. Lights on van on, trailer lights on and so on. But all this is intermittent. As we are driving, the light on the electric brakes sometimes flashes red but never turns to green and the brake lights nor the flashers work. The fuse did not burn out again.

Do you know what it could be???

Thanks in advance...

Answer
Without knowing the exact wiring, pin hookup and a digital volt meter my best advice is a electrical mechanic or closet rv service center. With that said, most rv camper plugs are a 7 blade hookup or is it a 5 pin flat (you mention e-brakes). Who did the install? It could be a simple ground problem, wire in a wrong pin or something more serious such as bad or old wiring if it's an older trailer. The only advice I can currently give without much speculation up is hooking up a true ground from the vehicle to the trailer frame (or ground in trailer wiring) and see if that helps if not give more information.