7Pin Charge Wire

[270S]

I know which wires do what (see pic)on 7Pin Plug on Tow Vehicle. I went to check used a diogital meter and discovered that the battery charge pin reads 0 volts with the engine runnig. Everything else appears just fine.

Is there something that needs to be wired in/on or something activated (fuse inserted) for that to work and read Alternator voltage (apx 14Vdc)?

[retiredcamper47]

Check under the hood of your tv for the fuse box. Using your truck's owners manual, locate the fuse/relay site for the "12v power charge to trailer". Bet you will find them empty. On my 2011 F150 with factory tow package, I had to install a relay and a fuse in the fuse box under the hood. Would have thought they would have been installed at factory due to the tow package. Hope this helps...............

Bob

[wanderingbob]

Some trucks come from factory with that pin hot some don't . As said above look under the hood . I had two 07 Rams , one came hot the other did not . By the way , Amazon sells a 7 pin checker , just plug it in and it lites up whats hot and whats not .

[RollingDownTheHighway]

is most trucks that is a separate power cable that needs to be connected to the battery. Check under the hood, near the batter for a cable that is zipped tied to a cross bar or hose. That is most like the power supply to that plug. I had to connect that cable to the batter in my 2010, 14 1500 Silverado's and my 16 2500

[Flybob]

If the fuse and the relay are not installed, check the glove box. Many times the fuse and relay ( if used) will be in the glove box.

[270S]

To all that replied, I installed a brake controller - That requires the 2 Red wires under the hood to be connected & the 4 under the dash. There are no others that I know of.


I've included a pic of the C/B box under the hood and I do not see anything related to trailer, hitch, ... power. The few empty positions are 68 (Stud 1 - possible if referrring to socket on hitch), 65 (elec Run Board - don't have), 58 (ALC/COMP - NO idea what this is), and PWR/TRN is installed, whatever that is again.


So no open items to be connected outside of possibly position 68, but there is no documentation I have found yet. Even the GMC dealer has no idea - he's checking.


I'll get a 40A fuse and put it in pos 68 and check if it will work.


Update - That was it! So for anyone with a 2008-? GMC Sierra , probably Chevy Silverado too, Position 68 Needs a 40 Amp fuse to power 12Vdc to Trailer. Considering, the TV had a towing package option installed, having no trailer brakes or wiring connected is ______.


Beacause the TV has a standard HO Alternator and was idle for a week or so, the voltage was apx 14.95-15.05.

[Flybob]

Yes in Chevy products it is stud 1

[270S]

Now the reason behind the original request - Where does this wire go (in the TT) after it connects with the TT's plug harness? Straight to the TT battery from the harness or does it somehow connect up to the CB/Fuse panels inside?


Apparently, the RV/TT industry does not like releasing any of this type of information. Just the opposite in the marine environment - they provide everything to the original customer. The trick is if the original owner keeps it properly in order to transfer the manuals and drawings to the subsequent owners.

[clr]

The battery charge lead from the TV will connect to the battery of the RV. I have never seen a RV that did not have this wire connected to the harness. Of course each model of RV may be a little different in how it connects to the RV battery. Most run the battery charge lead directly to the positive post of the battery. From the battery positive post you will have a large red cable going to a distribution bar for the RV this is the normal connection point for the charge lead to connect.

[Flybob]

In some units, it goes directly to the battery positive terminal. In some it goes through a resettable breaker usually mounted to the frame near the end of the Bargman connector cable.

[HONDAMAN174]

Mine has what flybob said


2014 Evo 2850 "Woodstock"
2011 Toyota Tundra "Clifford"