Is tow vehicle battery power sufficient???

[thatfeybabe]

Hi there,
This is my first time posting and I confess to being a complete rookie. So please pardon my ignorance... The demo of my 1974 Ambassador Land Yacht included removing the UniVolt, 12V distribution panel, RV battery, and basically everything electrical aside from the wires and exterior lights. My question is, will just attaching the 7-pin connector to the tow vehicle provide sufficient power to the exterior lights/signals (& brakes??) for towing? (ie Can I use just the TV's battery?) Also, where do I connect my white/ground wire? And is it necessary to connect the blue/charge wire if I don't have an RV battery to charge?
Thanks all!

[azflycaster]

The exterior lights and rakes are all powered from the tow vehicle and not the electrical system in the trailer. The only thing additional required for legal towing is a break away system to stop the trailer if it gets away from the tow vehicle. This would require a switch to activate the brakes and a battery on the trailer to energize the brakes.

I assume that you will install an electrical system as part of your restoration.

[thatfeybabe]

Originally Posted by azflycaster

The exterior lights and rakes are all powered from the tow vehicle and not the electrical system in the trailer. The only thing additional required for legal towing is a break away system to stop the trailer if it gets away from the tow vehicle. This would require a switch to activate the brakes and a battery on the trailer to energize the brakes.

I assume that you will install an electrical system as part of your restoration.

hi richard,

thanks for your quick response and the reassuring information. i had thought that was the case, but when i tried to hook up wires individually to a 12V jump starter/power source to see which lights they corresponded to, nothing happened. same with the power hoist. i suspect it is something to do with the ground... (i'm attaching the 12V ground to the chassis; do i need to something with the white wire inside the trailer????)

and yes, i do plan to redo the electrical. i was a little gung-ho ripping things out. i'll be mostly stationary, so was planning on shore power only...

thanks again!
babette

[Belegedhel]

Welcome to the Forums!

No, you don't need the blue wire hooked up, even to the 7-pin if you don't have a battery to charge (in fact, its best that you disconnect it altogether to avoid a short). The white wire is your ground, and you want it attached (at a minimum) to the shell. The factory arrangement had the ground going to the frame.

Something to note, is that this era of trailer was not wired for lights and brakes consistent with modern standards (neither the colors of the wires, or the arrangement of them in the 7 pin connection). So your first challenge is to figure out which wires go where (a wiring diagram from your owner's manual or service manual will help), and then reconfigure your 7 pin plug to be compatible with modern standards.

good luck!

[davidz71]

Just a thought, if the trailer were to become detached from the vehicle while you were towing it to a destination, the brakes do not have an electrical system to energize them since the umbilical cord will have also become detached. You now have a runaway trailer with no way to stop it. I see this as a risky proposition unless you are towing it down a farm road just a few miles.

[Bill M.]

What Richard said.

You will need a charged battery in the trailer hooked to the break away switch to lock the brakes in case the trailer comes loose somehow. Just one circuit. The running lights are powered by the TV and the trailer brakes powered by the TV when it is attached.

[uncle_bob]

Hi

Lots of stuff in the trailer runs on 12V and gets bothered if it goes away. Even without the (very important) break away issue, having a 12V battery onboard keeps a number of things happy as power goes in and out. One example is your fridge ( 12V control board goes down and likely resets to "off" when power goes away). Some furnace controls work the same way.

Bottom line - it's tough to get away from a battery and 12V system in a trailer that is set up anywhere near normally.

Bob