I'm towing a 2000 Saturn with a 2004 Fleetwood motor home. I'm triing to hook up the wiring to lights on the Saturn. The M/H has a 7 wire plug and Saturn has a 4 wire plug. I can't get the brakes lights to work on the car. I have bought a 7 connector for M/H and it goes a flat 4 plug to go to the Saturn.Why will the brake lights not work?

wire right into the factory towing package and unhook the battery while plugged in,
http://www.gmupfitter.com/publicat/2005_BB/2005_MD_C_Elec.pdf

some van don t have a ground wire. hook up to trailer put jumper cables to frame of trailer and van if works install a ground wire plug

Exterior lights are power by tow vehicle, or you can hook to 12Volt battery or charge circuit. When your unit is plugged to hydro you should have one tab on tow plug that has +12vdc coming to it from converter circuit in trailer. Find that with a test light or meter, then when your sure you have proper wire in plug for running lights, use a jumper wire from one to the other to power lights temporarily while you find each problem with running lights .

I am guessing you mean the 7 pin trailer tow adapter.

the 7 pin RV plug itself



The 2005 trailer tow adapter wire diagrams

if you go to the parts store they make them ready to plug in you will have to just unplug the tail lights and plug the wire harness inplace of it then itll plug back into the original spot.

I tow my 2005 Jeep Wrangler behind my motor home. I installed a Jeep trailer towing wiring kit to the rear lights. the bought a long trailer wiring kit and ran it from the front of the Jeep to the Jeep tralier wire plug. Pluged it in and pluged the other end into the motor home trailer light recptacle. I used only four wires plus ground. There is probably a way you could tap into the wiring harnes under the hood but not having a wiring diagram this is the best I could come up with and all lights do work. You can buy a test plug with led lights that plugs in both male and female, real handy for checking connections.

Also try http://www.etrailer.com/faq-wiring.aspx. They have a great website with lots of info. With the tow package, there should be a plug under the dash... far left above the emerg. brake petal. The harness that plugs into it should have came with the truck, or you can order one to fit it. Did thew truck come with a 7 pin plug on the back? If not you can order one from the above mentioned site. They also have the wiring colors.

directly to tail lights in trunk with a four pin attached to car light wires and then u run long seet of wires with male at one end and female other end and connect when needed to connector in trunk and to receiver connector

so, the trailer has no brake lights, or turn signals, just tail lights? Everything (all lights) on truck work ok? What do you have for trailer wiring hook up 4, 5, 6, or 7 way? There is no fuse, the lights all work off the tow vehicle lights, so if the tow vehicle lights all work properly, it's probably a wiring problem, such as bad grounds, loose connections, etc. Get a volt meter and check voltage at truck plug to see if power is getting that far. If truck plug in is ok, wiring problem is the trailer. Make sure all grounds are tight and rust free, that's a common problem.

I take it the blinkers and brake lights work ok when not hooked up to the trailer? If yes, then the wiring to the tow hitch is not hooked up correctly. How many wires to trailer pig tail connection? U can have up to 7 depending on what you tow. Check to make sure these wires are hooked up from the truck to tow plug correctly: 7 wired---
brown-Rt turn and brake light, yellow-backup, white-ground, blue-electric brake, green-tail running lights, black-battery charger, red-left turn signal and brake light. Let me know if u have something other than 7 wire, I'll get the wiring color and source info for u.