Posted 2007-05-19 1:25 PM (#1933) Subject: pre wired new trucks
Posts: 353
Location: indiana
I bought a new truck, Ford and am having the same problem that 2 of my friends have (one has a dodge and one a chevy) so I know it isn't the brand of truck. All these newer trucks come wired with the plugs that fit all the new trailers. The biggest problem is that none of us can use our interior lights or load lights anymore. Can anyone explain which wire is missing? All of them work on the old truck which we had wired for the trailer but we were told when we bought this new one that all the trucks had universal wireing?
Posted 2007-05-19 2:18 PM (#1934 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 85
Location: Arkansas
Your 7 way plug should have a constant hot wire on the center post..........are you using an adapter between a 7 way on the truck and a 6 way on the trailer? If so, your truck "hot" wire may not be in the correct position through the adapter....(this usually winds up activating the brakes when the adapter is cross wired)
I would first take my test light and find on the truck receptacle if there is a constant hot wire when the key is off. good luck....and keep us posted
Posted 2007-05-20 8:10 AM (#1936 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 353
Location: indiana
Originally written by flyinghfarm on 2007-05-19 3:18 PM
Your 7 way plug should have a constant hot wire on the center post..........are you using an adapter between a 7 way on the truck and a 6 way on the trailer? If so, your truck "hot" wire may not be in the correct position through the adapter....(this usually winds up activating the brakes when the adapter is cross wired)
I would first take my test light and find on the truck receptacle if there is a constant hot wire when the key is off. good luck....and keep us posted
I will use the test light, they told me that I could use an adapter and not have a problem. But, then I didn't try to pull the trailer so I don't know if my brakes are locking up. I will try that first and get back with you.
Posted 2007-05-20 8:45 AM (#1937 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 493
Location: Utah
I know on my Ford the hot wire is ONLY hot when the key is on. This is to prevent your trailer from discharging the battery when the truck is not running.
Posted 2007-05-20 9:09 AM (#1938 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 11
Location: colorado
We just purchased the new Chevy and had the gooseneck hitch put into the truck. All wiring worked, brake lights, tail lights, turn signals, BUT, no interior or exterior lights. They told us Chevy puts a dummy 30 amp fuse in the panel to run the hot that comes back thru the plug. We put in the fuse and presto it worked fine. Now why they didn't fix it at the shop we will never know, but try the fuse.
Posted 2007-05-20 10:46 PM (#1940 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 85
Location: Arkansas
Our constant hot wires are all ran through a relay (for short protection) and are hot all the time. This is our preference and probably not stock on the new prewired trucks........a dummy fuse ..... well what will they think of next! Glad you are fixed up now!
Posted 2007-05-22 9:10 AM (#1941 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 353
Location: indiana
Okay, my husband had to rewire the adapter and now everything works just fine. All lights and all, the brakes were locking up so you guys helped me out a big bunch. Thank you so much.
I will tell my friends with the Chevy and Dodge to check for dummy fuses.
Posted 2007-05-22 10:31 AM (#1942 - in reply to #1933) Subject: RE: pre wired new trucks
Posts: 1563
Location: North Carolina
Originally written by valerie on 2007-05-22 8:10 AM
I will tell my friends with the Chevy and Dodge to check for dummy fuses.
It's not a dummy fuse in the my Chevy. It is a genuine fuse. I believe the factory leaves it out until the consumer decides to make the system live... Otherwise there is just another point for the electrical system to fail or get damaged if a mis-wired trailer is connected... (There is no standard that says the center pin is the aux power. Some trailers have the center pin as the brakes)
pre wired new trucks
