charge lead from motorhome to toed

[03winniead]

I tow a 2012 Honda CRV with a Roadmaster BrakePro that plugs into the 12V outlet on the CRV consul, behind my Winnebago gas motorhome. After I tow 100 to 200 miles the battery in the Honda goes dead. I've been told I need a charge lead from the motorhome to the CRV. I need information on how to do this. Any help would be appreciated.

[j-d]

More I think about this, I'd want a relay or some solid state device (that I am incapable of understanding much less designing) that would isolate the two vehicles' batteries when the coach was not running. Otherwise, leaving something ON in either vehicle would run both down.
Starting toad with coach not running (and a relay or such) would not affect the charge line. Starting coach with toad connected would, unless the ACC terminal isn't powered while key is in START which might be true.
Maybe just too cautious... I just think about one vehicle's battery getting low somehow and the other battery trying to crank that vehicle through the charge line. But if all it does is blow a 10A fuse, not so bad...

[DaveG39]

If the charge line is doing its job the car battery will remain charged and the charge line will not overheat. If you are concerned, you can disconnect the umbilical before starting and the charge line will be an open line and not be able to overheat. Then reattach after starting. You would only need to do the starting while tied to motorhome when towing for longer in a day than the car book recommends between starting and putting car through gears.

[Olddud]

I installed a charge line from my Winnebago Cambria through the 7 pin connector and then to the battery, using 12ga. wire. It is fused at 10amps at the battery.

Recently, I had a Brake Buddy failure where it ran continuously for 30 minutes and nearly burned up the connector inside the Jeep. The fuse held on the charge line. So the charging line must have never exceeded 10amps. I have since wired a new connector made for the purpose for the BB.

[Sooboy]

j-d wrote:
Those with Hondas are supposed to start the engine and go through the gears every so often, right? Does the charge line have to be disconnected? I can see where if one battery was low, the charge line would try to act as a jumper cable and get really hot.

I have a charge line setup like FIRE_UP suggests in his post above. Just came back from a trip to Moab, UT and back....and experienced no issues. I've never unhooked to start-up and go through the gears.

[FIRE_UP]

j-d wrote:
Those with Hondas are supposed to start the engine and go through the gears every so often, right? Does the charge line have to be disconnected? I can see where if one battery was low, the charge line would try to act as a jumper cable and get really hot.

j-d,
Well Sir, yes the Honda manual, if I recall, mentioned something about only towing for around maybe 6-8 hours or so and then a break was needed to start it up and run it through some gears. I can't remember and someone that's still towing one I'm sure will verify or correct me on that.

Now, as for your assumption of the "charge line" acting as a jumper, well, if it's doing it's job correctly, as in charging the CRV battery, then the Honda starts in about 1-2 seconds, each and every time so, the potential for that charge line getting over heated because it's still connected to the coach, I think is nil. Besides, I (along with most folks) installed a fuse in it so, there's a built in safety factor there too.
Scott

[j-d]

Those with Hondas are supposed to start the engine and go through the gears every so often, right? Does the charge line have to be disconnected? I can see where if one battery was low, the charge line would try to act as a jumper cable and get really hot.

[FIRE_UP]

DaveG39 wrote:
I used 10 gauge - easier fit into connector.

Yep, I agree, the 10GA will work just fine. We towed our '11 CRV all over the western U.S. with a charge line in place and never pulled any fuses. That Honda engine started perfectly fine, each and every time. A check every now and then at the positive post of the CRV battery always revealed between 13.2 and 13.7V. while hooked to the coach and the coach running.
Scott

[DaveG39]

I used 10 gauge - easier fit into connector.

[astro001]

I used 8ga.

[dicknellen]

For you that have done a charge lead, what gage wire did you use?

[astro001]

I connected the charging wire on my 2011 CR-V via a 50 amp breaker. No dead batteries or problems in 3 years, including towing several 14 hour days.

[obgraham]

There is already a ground wire within the coach-to-toad harness.

[dicknellen]

Is their any need to also run a wire to the neg battery terminal on the CR-V? Will a # 14 wire be enough to keep the battery charged?

[Beverley_Ken]

I agree with adding the charge line, especially with and aux brake unit plugged in. Even with pulling the recommended fuse, the Honda battery will not last. We accidentally left a reading light on while getting groceries and within a hour the car would not start. Also if we don't start the car for 3 or 4 days, dead battery. Canadian Honda dealer says no problem, wont replace under warranty, Florida Honda dealer says the battery has a short in it and needs replacing but the cant do it under warranty, want big dollars.

Your Winnebago should have a charging 12v already in the 7 pin receptacle. The 12v is only live, when the MH is running. We added a line from the CRV receptacle to the Honda battery, 15 amp fuse just before the battery. No problems when towing.

Beverley and Ken