Trickle Charge for Towed Vehicle

[Village Guy]

I have a 2014 Ford Edge that I am towing behind my 2016 Newmar 3214. The car has to be started every 4-6 hrs and run to recharge the battery. We are planning a very long trip to Alaska this year and I think this will be a real pain when on the road for several days at a time. I want to try a trickle charger and have thought of everything from a small 110v battery maintainer that I would have to power from the coach while on the road, to (probably a better idea) getting a solar trickle charger. The problem is I have no idea how much the battery is being drained while going down the road (have to leave ACC on) and what size trickle charger I might need.

Anyone have any experience doing this with suggestions????

Thank You

 

[Neemer]

Have you considered a charge line off the coach’s batteries? That’s what most do including myself.

 

[Village Guy]

Sorry, but not sure what you mean by a charge line? The tow system I had installed has a line (in the power plug) that is supposed to feed power back to the tow vehicle, but it apparently is not adequate to replace the power used and my battery went dead after about 5 hrs. (Battery is close to 3 years old, so may replace it before the trip). Do you mean you run another a separate line from the coach batteries back to the tow vehicle?

 

[TJ&LadyDi]

I don't know the Ford Edge specifically, but is the ACC on just because the key has to be in that position to unlock the steering column? Or, is there something in the toad that needs to be powered from the ACC position (lights, brake system, etc.)?

On our Honda CR-V, we have a battery disconnect relay that operates automatically when the coach-to-toad electrical cable is plugged in. The 12V power from the coach powers the tail/brake/signal lights via the "charge line" mentioned by @Neemer. That's a common/preferred setup to keep the toad battery from discharging.

Obviously, if there is something about the Ford Edge that requires power from the battery, that approach won't work. Usually, however, the toad's lights can be set up to work off the charge line, or to use separate magnetic-mount brake/tail/signal lights. I would consult a qualified RV shop to see if your toad can be set up this way.

TJ

 

[Neemer]

OK. Several points to talk about.

1. Welcome!

2. Please fill out your profile to include information regarding your rig and toad. That helps us with answering questions you may have.

3. Given the age of your battery, I would have it load tested. It’s entirely possible you just need a new one. If you want, you can pick up a load tester at places like autozone for not much money. They are handy to have.

4. Take a voltmeter and make sure there is 12v power going to your car battery from the motorhome. Just trace wires to find the correct one. When you find it, make sure you are either plugged in, running the generator, or running the engine to properly test it. As an aside, not all manufacturers provide that 12v line. Mine didn’t.

5. If you find you do not have 12v power going to your car’s battery, there are a couple of easy remedies for that which we can talk about if that happens to be your case.

I pull a 2012 Taurus and the coach keeps the battery charged just fine with the key in ACC position and an aux braking system that also puts a small drain on the battery.

 

[lemondrop9344]

You state you need to leave the ignition switch on ACC when the vehicle is towed. This would seem to suggest something needs 12 VDC while you are going down the road. Do you know what requires power? For example, my Jeep Cherokee requires the electronic power steering be activated while being towed.
I use a combination of a 15 amp auto reset breaker & a simple on/off switch to keep the battery charged while the vehicle is being towed. If I don't disconnect for the night, I turn the switch off.
Do you know if the battery in the towed vehicle is getting power from the RV? In your post above, the operative words are 'supposed to feed power back to the tow vehicle'. I would never assume that anything I had to pay someone to do for me was done correctly until I verified that it worked. This is especially true with anything associated with a RV or a boat.
Do you have a muli-meter? If you don't have one on the RV, I would encourage you to acquire one.

 

[Village Guy]

OK. Several points to talk about.

1. Welcome!

2. Please fill out your profile to include information regarding your rig and toad. That helps us with answering questions you may have.

3. Given the age of your battery, I would have it load tested. It’s entirely possible you just need a new one. If you want, you can pick up a load tester at places like autozone for not much money. They are handy to have.

4. Take a voltmeter and make sure there is 12v power going to your car battery from the motorhome. Just trace wires to find the correct one. When you find it, make sure you are either plugged in, running the generator, or running the engine to properly test it. As an aside, not all manufacturers provide that 12v line. Mine didn’t.

5. If you find you do not have 12v power going to your car’s battery, there are a couple of easy remedies for that which we can talk about if that happens to be your case.

I pull a 2012 Taurus and the coach keeps the battery charged just fine with the key in ACC position and an aux braking system that also puts a small drain on the battery.

Ok, Thanks for the Welcome. I filled out the information in my profile. I had thought about getting a load test done, but the battery has so far shown no signs of being weak under normal use and we have no trips coming in the next 30-60 days, so see no reason to rush replacing it.

I did check the plug and there is power going through. The shop that installed my tow package had me check that early on and I used a voltmeter to check it. Don't remember how much, just that the position that he told me to check had power. They also told me that it would be almost likely that it would not be enough to keep the battery charged, based on the prior history they had seen with Ford Edges. So, I am open to whatever the easy remedies might be!

 

[osuallen]

Do you have to leave ACC on only to keep the steering wheel unlocked or is there a power reason as well? If it is the former, then a battery disconnect along with the charge line from the coach should provide adequate power to keep the car battery topped off.

 

[Village Guy]

Thanks---that makes sense---I'm not certain why the key has to be left in that position and the manual only says it has to. I will try to find out what the reason is---

 

[amullis59]

My 2018 Ford Explorer has a feed line from the coach to keep the battery charged up. The battery is disconnected after placing the transmission in neutral. I never have to stop every few hours and run the Explorer to charge the battery back up.