Posted 2006-08-06 10:26 PM (#46117) Subject: Where's my 'ground' wire?
Member
Posts: 45 Location: Houston, TX
I have this posted as another topic (trailer wiring help needed...).In rewiring my trailer plug, I *cannot* find a white wire that should be my ground within the wires of the cable. I have all the rest - just no white? The plug is a 7way RV plug which has a terminal (white) for ground. The same plug and cable of wires had been used before and worked. (I had an oops and pulled the plug off of the cable.)Thanks again for all your help!Nathalie
Posted 2006-08-06 10:45 PM (#46119 - in reply to #46117) Subject: RE: Where's my 'ground' wire?
Expert
Posts: 2689
Originally written by threehorses on 2006-08-06 10:26 PM
I have this posted as another topic (trailer wiring help needed...).In rewiring my trailer plug, I *cannot* find a white wire that should be my ground within the wires of the cable. I have all the rest - just no white? The plug is a 7way RV plug which has a terminal (white) for ground. The same plug and cable of wires had been used before and worked. (I had an oops and pulled the plug off of the cable.)Thanks again for all your help!Nathalie
It doesn't have to be white.
As someone I once worked with used to say, "The electrons don't care what color covering is on the wire."
According to where your trailer was made it might be black or green, the best way to find out is to open up the other end of the cable, failing that BUZZ it. Just remember that lights and brakes are very low resistance, so you'll need a decent meter.
Posted 2006-08-06 11:31 PM (#46120 - in reply to #46117) Subject: RE: Where's my 'ground' wire?
Veteran
Posts: 143 Location: southeast U.S.A.
Nathalie,
I believe in Your previous posts You stated that this trailer has only six wires and You're using a seven way RV type plug. I still can't tell You without testing the connections which one is the ground but i'll give You a little further information that may help if you can find the ground. When a horsetrailer is wired with 6 wires they should be a wire for the following:
GROUND
LEFT TURN
RIGHT TURN
TAIL/RUNNING LIGHTS
+12 VOLT FEED
BRAKE CONTROLLER
As to your original question, The ground could be any of the colors,depends on how the manufacturer decided to use the colors in this trailer,
Posted 2006-08-06 11:48 PM (#46121 - in reply to #46117) Subject: RE: Where's my 'ground' wire?
Veteran
Posts: 143 Location: southeast U.S.A.
Nathalie,
I have to ad an additional note on the wiring trouble that You're having, As I stated in the previous post it is very important to get the brake controller and ground wire in there proper place. Speaking of the type controller that I use,it's stated in the owners manual that if it is backfed that it can destoy the controller which could be very costly to You to replace.
If You're that unshure of how to rewire the plug I'd keep that in mind not to mention that if You mistakenly used a lamp for the ground it would cause a voltage drop across everything else including the brakes.
Posted 2006-08-07 12:53 AM (#46123 - in reply to #46117) Subject: I did it! :)
Member
Posts: 45 Location: Houston, TX
53 I can't believe it, but I figured it out.
In case anyone else has to change a CM 6-way wire into a standard 7-way RV plug, here's what I did.
First, I tried *again* to find the schematics for trailer plug wiring at the CM site. This time I found them:
I wrote down which function each color of the 6-wire represented (blue=ground, black=brakes, etc). I noticed that CM's 7-way plug didn't match mine (I have no purple or white wires) so I knew I couldn't use their diagram. So I went looking for a standard (aftermarket) RV plug and found it here instead: I used the chart and wrote down which numbers went with which colors (1-white, 2-blue) and compared it to the imprint on my plug. It was a match.
On a piece of paper, I wrote 1-ground, 2-brakes, etc from the same chart. Then going by my list from the CM site, wrote down which color wire fit the function shown. (1-ground-blue, 2-brakes-black, etc) I hooked those babies up according to my list, and they worked!
So tomorrow to our unexpected vet trip, at least I don't have to worry about whether or not I'll have brakes/lights/etc. They all checked out good.
Posted 2006-08-07 7:43 AM (#46137 - in reply to #46123) Subject: RE: I did it! :)
Expert
Posts: 2689
Originally written by threehorses on 2006-08-07 12:53 AM
53 I can't believe it, but I figured it out.
In case anyone else has to change a CM 6-way wire into a standard 7-way RV plug, here's what I did.
First, I tried *again* to find the schematics for trailer plug wiring at the CM site. This time I found them:
I wrote down which function each color of the 6-wire represented (blue=ground, black=brakes, etc). I noticed that CM's 7-way plug didn't match mine (I have no purple or white wires) so I knew I couldn't use their diagram. So I went looking for a standard (aftermarket) RV plug and found it here instead: I used the chart and wrote down which numbers went with which colors (1-white, 2-blue) and compared it to the imprint on my plug. It was a match.
On a piece of paper, I wrote 1-ground, 2-brakes, etc from the same chart. Then going by my list from the CM site, wrote down which color wire fit the function shown. (1-ground-blue, 2-brakes-black, etc) I hooked those babies up according to my list, and they worked!
So tomorrow to our unexpected vet trip, at least I don't have to worry about whether or not I'll have brakes/lights/etc. They all checked out good.
Thanks again, y'all, for all your help!!
Nathalie
Congrats, not how I would have done it, but if it works... it works.
Just be sure to check what happens when you pop the truck into reverse.
ONE posssibility is that the fuse for the back-up lights blows because it is supplying FULL current to the trailer brakes. It might not blow, since the trailer brakes only draw about 12 amps, so the symptom might be that you just can't back up. Other possibilities - are possible (-:
Where's my 'ground' wire?
Thanks again for all your help!Nathalie
