I have read a great number of comments about keeping br Towed's Battry charged whole underway but still have a few questions from the experts on this. Forum!#1. I have a live when Key On Circuit and connected it via a 10 Amp Fuse to the connection that I am using on the 7 Way Plug ...which connects to the Toad!So with due diligence I have 12-14 Volts plus as far as the front Bumper!Now here is where I chose to Stop! Do I need a Diode as wel as a fuse before connecting to the Toad's Battery?I'm concerned about feeding an overload to the toads Electrical system! Any advice?.

The diode might come in handy as it would assure that once the vehicle is stopped and off, the towed's battery will not be drawn down to share with a weak chassis battery. A diode will also lower the voltage received by the towed. Your vehicle's charging system is a regulated system. When the towed battery and chassis battery are fully charged, the vehicle's alternator will not push any more current then is necessary. Unless you have a failing chassis battery, it is nearly impossible to damage the towed's battery.

I hook ignition-switched power from the motorhome directly to the dinghy battery, fused on both ends. No diodes, and no problems after a few years of use.

what is on in the toad that draws so much juice it runs down the battery? I used a brake buddy and plugged it into a small jumper/starter battery thingy that I wanted along anyway.bumpy

A fused wire connected to the toad positive terminal takes care of keeping mine topped off when underway. A charging wire is needed by most new model toads because of all the computer related stuff that can't be shut off.

Thanks for the answers.Maybe I'm just being overly cautious, but reading about Towing the newer Cars with all their Electronics and such has Me a bit more concerned. Our Old Toad ...A 92 Tracker was easy if and when the battery failed I could just jump start it!It is nearly impossible for Me to reach the Fuses in this New to Us Honda CRV to either pull Fuse #XX or install a Switch to do that.I figured I would just tie in to the available power supply on the Motorhome and keep the Toad supplied with juice.I have to also consider what else may be connected to the Keyed 12 Volt power source. Just in case something gets fed power back from the Toad end .That is why I thought a Diode might be the answer however if it lowers the charge then maybe is not such a great idea.A simple Switch or relay would also work ,however that might get forgotten at some point which would defeat the purpose entirely.Of course just unplugging the Cable is also an option,but then again ??I may just have to rethink the power supply point and install a dedicated circuit that has nothing at either end which can get fried!

Keeping Tow Car Battery Charged while Towing! | Good Sam Community

beemerphile1
Explorer
Oct 09, 2014
smkettner wrote:
Just connect the 12v power direct. Put a fuse at each end and you are good to go.

Amen to the above, why make it so complicated? The two systems will work harmoniously with no issues.
time2roll
Nomad
Oct 09, 2014
Just connect the 12v power direct. Put a fuse at each end and you are good to go.
robatthelake
Explorer
Oct 09, 2014
Today I installed a Switch to disconnect the Radio Etc . That was not an easy feat for this Old Boy.
That said the job is done and I will feel better about towing the Honda. Cost was about $15!cad.

I will still be installing a charging circuit to keep the battery up but now will have the time to properly research the situation.

I have looked at the RVI charger for $50 US and the. rectifier route for about $5 ,there are still Diodes for about the same $5.

I guess that I am still a DIY kind of guy and also somewhat Thrifty so will keep looking!
robatthelake
Explorer
Oct 05, 2014
I guess I should have mentioned the possible feedback to the Motorhome from the Toad as another concern in My original post!

There may be other equipment on the Live with Key Circuit that could possibly be harmed ,now I'm not so sure that it is a good enough connection.

That isn't just a Battery charger it is also an isolator so makes perfect sense!
ScottG
Nomad
Oct 05, 2014
smkettner wrote:
robatthelake wrote:
I'm concerned about feeding an overload to the toads Electrical system!
The RV and car alternator charging systems operate virtually the same.
No harm will ever come from direct 12v power to the car battery.

It cannot overload the toads system because the toads battery takes what it needs - it's not force fed.
pigman1
Explorer
Oct 05, 2014
Wayne Dohnal wrote:
I hook ignition-switched power from the motorhome directly to the dinghy battery, fused on both ends. No diodes, and no problems after a few years of use.
Yep. me too. We've run this setup since 2006 on 3 separate coaches with 3 different toads. Never a problem.
deltamaster
Explorer
Oct 04, 2014
bstehmy wrote:
I went with the RVI system:
http://www.rvibrake.com/RVibrake-Towed-Battery-Charger-p/tbc-12014.htm

Brake Buddy has a less expensive one.

So I have a 12 volt lead on the back of the RV.

I mount this device in the towed vehicle and connect it to the battery.

I feed this device with the 12 volt lead from the RV and it regulates the charging of the towed vehicle battery whenever the lead from the RV is connected.

Does the same thing as connecting the 12 volt lead directly to the battery except it is regulated?
robatthelake
Explorer
Oct 04, 2014
bstehmy wrote:
I went with the RVI system:
http://www.rvibrake.com/RVibrake-Towed-Battery-Charger-p/tbc-12014.htm

Brake Buddy has a less expensive one.

Now why didn't I see that before? I guess because I'm the type who tries to invent stuff myself . It never occurred to Me that somebody might actually have a product that would do the job.

Thank You!
time2roll
Nomad
Oct 04, 2014
robatthelake wrote:
I'm concerned about feeding an overload to the toads Electrical system!
The RV and car alternator charging systems operate virtually the same.
No harm will ever come from direct 12v power to the car battery.
Bumpyroad
Explorer
Oct 04, 2014
deltamaster wrote:

I am also wondering if there is a better way to do this that is simple and easy.

IMHO yes there is. buy a small jumper/starter jobby.
bumpy

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