Hi Gang, I have an oldish (1977) van and have been attempting to fix the lighting. When I bought the van, all the lights etc. were working except for 3 of the clearance lights. Now the only things working are left and right indicators, number plate light and left rear clearance light. I am not sure what has changed. Upon opening the 7 pin flat plug, the coloured wires are all in the wrong order except for the white earth wire. The previous owners must have swapped the colours around. As I said, up until recently everything worked except for 3 of the clearance lights so even though the colours are in the wrong order, the actual wires must be correct. I also noticed that where they had joined the wires up higher that there were 6 wires. The extra wire was a thick green wire. In the 7 pin flat they have used that wire and the red wire has been cut off and not used. It's all very confusing. I hope the photos attached explain. Does anybody have any idea how I can check why some of the lights work and why most were working but now do not. I looked underneath the van to see if I could rewire it but all the wires are inside the walls of the van with no access. Thanks for any suggestions you have!!!
The worst problem to have!!! Always a pain sorting old wiring out. At that age, much can vibrate loose, or as mustang suggests corrode. There will be no quick fix I suspect except to use your multimeter and find out If each wire is actually intact, from pin to light globe. Having different colours of wire connected together doesn't help. As mustang suggested, find where your earth is attached to the chassis and reseat if corroded. Then go to each of the other lamps and make sure they are OK and their contacts are nice and clean. Sand off any rust. AS you check each line and made sure they carry power, write down what each wire is. Then make sure each wire corresponds with the number in the plug. If it still doesn't work check that the wiring in the socket agrees with the pin.
Above all, HASTEN SLOWLY!
Last Edit: Aug 25, 2020 16:45:36 GMT 10 by Roehm3108
Thanks for the replies! I guess I need to buy a multimeter and figure out how to use that lol. I'm also trying to figure out how the 12v works. There are 12v lights and switches in the van but no 12v wire that I can find and no connection anywhere. Unless it was the red wire that they have cut off? I'll try a few more things myself but I'm heading towards getting an expert in.
Well I have more problems! When looking to see if I could find the end of the 12v wire from the internal lights I found some wires in very bad condition. As I can't see inside the railing I'm not sure how far the damage goes back. Looks like I need a whole rewire. Waaaaaaah!
BUGGER!!!! Could end up being a blessing in disguise! If you haven't pulled the old wiring out, you may be able to use them as a "pull-through" for the new wiring. Get colour correct wiring for each lamp and attach one end securely to the old wire and pull it through. Use solder to keep everything as thin as possible so that it goes through easier. You can buy each colour correct wiring by the roll and then connect it together on the 7 wire loom under the van.
When I rewired our Travelhome, I had taken the outside fridge vent off and found that the wires were accessible from there as they were routed through the floor. I ran a new seven core through the A frame tube to the same spot, and then joined them under the front seat using a seperate fuse for each major wire. The 12 volt wire went from there up the wall cavity to the front inside light and the outside light, and then through the roof to the rear light.
Hi again, the van is so old the fridge vent is open to the inside of the van (you can see outside through it). All the wires run into the trailer underneath never to be seen again. If I attach new wires to all the old ones will they all pull out separately? Or are the clearance lights joined in a loop together? Will there be some type of junction inside the trailer where the wires split to do the left and right sides (brake lights etc.)? Wondering if I should give it a go or get a professional in. Thanks again!