Maintaining Dinghy Battery

Batteries and some big breakers are usually at the rear corner.
I would ask factory, even though we haven't, but we didn't do our own.
They should have info on best take off, as almost all RVers tow a vehicle.
There may even be a wire or fuse specified for it on later ones. Someone here know?
The plug has seven pins and most seem to use a 7 pin round to four pin round cable and plug for the little four pin round receptacle.
Seems there are three wires available for something.
It would seem you could wire from battery or fuse on towed to a five pin? receptacle, and a 7 pin to five pin cable and adapter plug.
Be simpler than fishing the single wire out from the grill on your knees and pluging into the dangling wire from the coach. Maybe the three extra wires are for electric brakes, I don't know. We use air brakes.

One thing you can do is replace your tail and marker lights with LED's to reduce the current requirements for turning, braking, and the running lights...all required by law when towing. Many states now require a braking system too. Which usually plugs into the toads cigar lighter outlet.

The prices of the LEDs have dropped quite a bit, at least on Amazon, making this a economical method of lighting.

Once the old incandescent bulbs have been changed over to LEDs, you'd need 3 more diodes, over what you may already use in the toad, 100 Volt @ 3 Amp is fine, around $0.15 each. You'd install them with their anode connected to the 3 incoming connections of your 4 wire connector on the toad (the 4th wire would be ground). The 3 diode cathode's are connected together to an output wire, a 10 Amp fuse added in line, then connect to the positive of the battery.

The low current required by the LEDs leaves enough charging current in those wires to keep your battery trickle charged enough to run any battery operated braking system you might get.

It would work best if you kept the running lights on, but no need for the RV's headlights to be on. Some RVs have the trailer connector wired so the Running light pin is always hot as soon as the engine is started so check for that. If it is, then you don't even need to turn on the running lights in the RV.

I installed the RVI Towed Battery Charger works great. Like YC1 said the Ford Edge is a power hog but I like it.
JR

Thanks for all of the responses. The new toad is a 2016 Jeep Cherokee. It replaces a 2003 Saturn that has finally bitten the dust after 200K miles.

I am aware of the fix required for the "wobble" issue. The fix requires the electronic power steering to be available while towing and that is what puts the strain the battery. Fiat Chrysler recommends charging the toad battery while towing, which is the reason for my question.

Thanks again. The amount of knowledge and people willing to share is amazing.

Replace your 4-pin flat trailer connector set with a 6-pin round utility or 7-way blade RV plug set.

Then you need to find a key-on/off source of 12v power at the fuse box of the coach, fuse it appropriately. Using a key-on/off source allows the trailer charge connection to be dead whenever the coach ignition key is off.

Run a 10ga or thicker wire from the fuse box back to the battery charge pole of the coach side of the new trailer connector.

From the trailer side of the connector, run another same size wire to the car's battery + terminal. Fuse this wire with an in-line fuse next to the battery, using same size fuse as you used at the coach's fuse box.

Run a same size ground wire from the battery - terminal to the trailer side of the connector.

From the coach side of the connector, run a ground wire to the chassis of the coach.

Oasisbob wrote:
Just curious as to why this might be important? Brake lights?

Some vehicles like my Ford Edge Limited are power hogs. The vehicle is left in neutral and with the start button put in the off position there is plenty of drain. The braking system can use a decent amount of power in a day too.
Any drain will also find a weak battery. It is a pain to pull in and find the battery dead.

I've done 5 East to West cross country trips with toads hooked up. At my pace, that takes anywhere between 6-8 days each way. Never unhooked the toad, never started the motor(s) and at my destination, they all started with no problem.

I guess the secret is to have a good battery in the toad.

Oasisbob wrote:
Just curious as to why this might be important? Brake lights?

x2

my vehicles sit in my driveway for hours/days on end without being hooked up to any charge. if it is to power a braking system like a brake buddy, I plugged mine into a small jumper/starter battery jobby which I wanted along anyway.
bumpy

Just curious as to why this might be important? Brake lights?

Definitely do not try to use the headlights as a charging source. There would be very little current handling and you could easily pop fuses often.

If you are not comfortable finding a source to tap have someone that is. You do not need to have it run through a relay, just a fuse close to where you pick up the power and one close to where you connect to the toad battery.

Disconnect the toad charge line if parking overnight if you do not have shoreline hookups.