Arrive at destination and toad battery is dead

Hi Folks,

We've had a time with our Honda FIT's battery.  I added a 12V DC line from the Cruiser's battery through the umbilical cord to the FIT, then from the umbilical socket on the FIT to the battery, through a fuse.  The intent was to power the GPS and other accessories in the FIT from the Cruiser, while towing, leaving the FIT's battery relatively unloaded.

The current problem is that, when we arrive someplace for the night, unless we unplug the umbilical when, the FIT battery is dead in the morning.  Diane had the idea to disconnect the umbilical when we arrive.  This prevents the dead battery while sitting in camp.

What seems to happen is that, when we arrive, we turn off the Cruiser's engine, leaving the umbilical plugged in to both the FIT and the Cruiser.  Then somehow, the Cruiser sucks current from the FIT's battery through that extra 12V line we added to the umbilical.

Some company makes a battery charger that will trickle the toad's battery, powered by a  line to the Cruiser, just like we have.  But, I don't want to add equipment (and cost) to the towing rig if I can avoid it.  I think a diode, which will allow current to flow TO the FIT's battery, but not FROM it would work.

Has anybody had such a problem?  How did you solve it?

Tanks in Advance!
Bill

Hi Bill,

We have the same condition with our tow vehicle, a Jeep Liberty.  When we stop for the night while remaining all hooked up like at a Walmart for example, I have to unplug the umbilical cord as well.  If I don't, the battery in the Jeep powers up something in the PC that I can't recall now.  I seem to recall it is related to the back-up camera and the tow brake system, but not sure.  I'll have to make note of it the next time we tow.

Bill

E-Trailer sells a Roadmaster park light diode ,RM-690 At $10.99.

We had the problem with our Fit. Solved the problem by running 8 gauge wire with a fuse from the battery to the PC's tow plug.

George

on my crv i've installed a "toad charge" it solved the problem.

you have to turn off the ignition key overnite. the first order of business after parking is to take care of the tow.

We have had that problem, first solution on old Jeep Wrangler was to install a flip switch on the battery and disconnect when we were on the road. That did solve the problem. And we always carried
a jumper unit... now we have a new 4 door Wrangler 2015 and some of the things that had to be installed come installed. Some diode and who knows what.. Anyway we have not seemed to have
a problem yet. The way things are hooked up on the new P C may give us cause for alert but not enough road experience to be convinced we have battery or not. We did about 1200 miles home from
Elkhart and the jeep cranked when it was disconnected so we have not had our lessons yet. We have a Roadmaster Sterling towing set up with an air braking system cylinder to allow our brakes to
work when applied in the PC same as when we had the class A.  we soon find out  if all works like we hoped. Good luck no tow car battery power  is something we put up with for a while. Patricia

P S  Did a trip over the weekend and things did work well coming and going. Trip was 2 or 3 hours but enough that if things were not working right we might have had  no cranking.

You might want to check with the folks at RVi (Brake Buddy) they have a super little unit (Toad Battery Charger) for $50.00 that installs in less than 15 mins and keeps the toad battery charged on and "as needed" basis, I think there is all so a built in feature that prevents flow back to the motorhome and the dead battery situation in the toad.  Great tech assistance at the end of their 800 number that will fix your issue for sure. Thanks, Ron G.