TOAD Electrical Question/Advice

[OldracerJim]

We use our 2020 Entegra Esteem 27U to tow our 2014 Ford Explorer. We flat tow it with a single limitation that the car must be run 15 minutes after 6 hours of towing. It appears the primary reason is to charge the battery. I have a Roadmaster Blackhawk 2 All-Terrain tow bar with a Roadmaster Diode 7 wire to 6 wire Flexo Wiring Kit.

My question is: I'm pretty sure there is an open pin from the MH. Can I add a wire to charge the car battery while towing it? Would that be a direct wire to the car battery from the MH pin or would I need some sort of terminal block in between?

[PDR John]

Yes, you can.

The RV should already have a battery connection on its end. Most of the 7 blade plugs have a diagram on the lid telling what each post is. You will just need to add the wire on the toad end. I always put a 20 amp circuit breaker just before the battery.

[OldJohnT]

Sure, you can add a charge wire so the RV supplies some degree (albeit perhaps limited in current and voltage due to line drop depending on wire size and length plus battery voltages and SOC) of charge back to the Toad battery. Ive done it on several vehicles for years just be aware:

1) The the current rating of the 7 pin connector, its NOT high !!!!
2) You could use either the RV house battery or the engine battery to feed it subject to what you have and charging requirements.
3) You should place an overcurrent protection device (fuse or breaker) at BOTH the RV and toad battery.
4) Some install a Diode in the line configured so the RV can pump charging current back to the Toad battery but prevent reverse current flow but there's a 0.6 volt drop across it.
5) Some use a relay instead of a diode for the purpose above

NOTE for example if you used say 20 feet of 10 Gauge Wire, due to line voltage drop and other factors you're not going to supply a lot of charging amps to the Toad but it may be enough for the small loads ... Its NOT a high charging amps situation ONLY to maintain the Toads tail lights and small electronics controls etc

John T BSEE,JD Electrical Engineer and 50 year RV owner

[youracman]

Originally Posted by PDR John

Yes, you can.

The RV should already have a battery connection on its end. Most of the 7 blade plugs have a diagram on the lid telling what each post is. You will just need to add the wire on the toad end. I always put a 20 amp circuit breaker just before the battery.

^^^^^ X2 ^^^^^

I did exactly the same thing. Some install a diode, but I didn't see the need (and a diode will normally drop about .7 volt across it.)

Good luck with your project and save travels.

I see John posted while I was typing.
What he sez.

[youracman]

You probably have this Jim, but just in case......... I believe this wiring setup is "std" in the RV industry for the 7-pin connector but not for sure.

[mb1956]

We just started towing our jeep. I went with Blue Ox for all towing parts. They have a charging system just for that reason to keep battery charged. We have the patriot 3 breaking system it needs 12volts of power full time. Have not had any issues with battery so far with 1130 miles car started right up. Yuo might look at blue Ox and see if it will work for you.

[groswald]

Originally Posted by OldracerJim

.... It appears the primary reason is to charge the battery.

As others have pointed out, it's pretty easy to keep the battery charged. I use RVibrake's charger and it seems to work quite well.

But, keeping the battery charged may or may not be the only reason to run the engine for 15 minutes. I'm a firm believer in following the manufacturer's towing instructions to the letter. The consequences of not doing so can be catastrophic (I know, personally, of one couple who's Jeep burned to the rims), and no warranty or service plan will cover the damage. So, why take the risk?

A charge line is a nice addition, but I'd still do the end of day engine run unless I could get Ford to tell me, in writing, that charging is the only reason to do so!

Regards,

Randy

[nodine]

Originally Posted by OldracerJim

We use our 2020 Entegra Esteem 27U to tow our 2014 Ford Explorer. We flat tow it with a single limitation that the car must be run 15 minutes after 6 hours of towing. It appears the primary reason is to charge the battery. I have a Roadmaster Blackhawk 2 All-Terrain tow bar with a Roadmaster Diode 7 wire to 6 wire Flexo Wiring Kit.

My question is: I'm pretty sure there is an open pin from the MH. Can I add a wire to charge the car battery while towing it? Would that be a direct wire to the car battery from the MH pin or would I need some sort of terminal block in between?

The reason Ford says to run the car after 6 hours is to redistribute transmission fluid in the transmission. They should ask you to run the transmission in reverse and drive before placing it back in neutral for towing. We have towed a Honda CRV and the manufacturer required this every 8 hours of towing. We now tow a Chevy Sonic and the manufacturer says do the same thing after every 8 hours of towing. We have towed two four wheel drive vehicles with a transfer case and you can tow them for weeks without doing anything because with the transfer case in neutral the transmission does not turn.

[OldracerJim]

Thanks everyone, this helps a lot.

[Farmboy666]

Originally Posted by nodine

The reason Ford says to run the car after 6 hours is to redistribute transmission fluid in the transmission. They should ask you to run the transmission in reverse and drive before placing it back in neutral for towing. We have towed a Honda CRV and the manufacturer required this every 8 hours of towing. We now tow a Chevy Sonic and the manufacturer says do the same thing after every 8 hours of towing. We have towed two four wheel drive vehicles with a transfer case and you can tow them for weeks without doing anything because with the transfer case in neutral the transmission does not turn.

From what I understand it’s not 8hrs of towing but every 8hrs. If you tow for 5hrs and then park for 5 more the trans fluid has drained away even though it’s only 5hrs of towing. On my Jeep I don’t need to stop but even though the transfer case is in neutral I leave the shifter in second gear it keeps the gears from running dry.

[nodine]

Originally Posted by Farmboy666

From what I understand it’s not 8hrs of towing but every 8hrs. If you tow for 5hrs and then park for 5 more the trans fluid has drained away even though it’s only 5hrs of towing. On my Jeep I don’t need to stop but even though the transfer case is in neutral I leave the shifter in second gear it keeps the gears from running dry.

You are correct and we understand that. I think the manufacturers are worried about the folks who put in 12 hour days on the road. Most of us are not like that and our typical day of towing is about 6 hours on the road. With that in mind we just go thru the gears each morning before we hit the road and that gets us to the next campground. When I was a young whippersnapper I did not think anything about doing a 14 hour drive. Those days are long behind us.

[Stevegd007]

Folks, it your interested. There is another solution. I have used for years. Its basically a direct line from your RV battery to the toad. Works great. Keep the toad battery fresh. Give it a look: TOAD-CHARGE Dinghy Vehicle Battery Charger/Maintainer
Requires a little work to install, but its easy. Comes with everything needed to keep the toad battery charged. Only issue I have ever had is a loose wire and that lost my power from the RV to the toad. Redid the wire and all is OK again.

[Farmboy666]

I made my own system on my jeep to keep it separate from the jeeps electrical system. I mounted a six way plug in the grill and ran a power wire to the battery and parking light, brake light, turn signal wires to the rear lights. Inside the rear lights I mounted Bulb holders. I now have brake lights and signal and parking lights just like it was a trailer. I have a seven way to six way coiled cord for a connection.

[Neverhome2]

We are running a line from our chassis battery to the 12 V charging line in the RV 7 pin connector. (PS: Don't run it from your house battery) The chassis battery has the alternator so your chassis battery won't deplete and the chassis battery will have the capacity to provide the additional charge needed to the toad.

Etrailer has a kit that is very simple to use and has the circuit breaker included. https://www.etrailer.com/Accessories...RM-156-25.html If you are handy, the parts can be purchased at a local auto parts store much cheaper. We had the wire and hardware on hand and just purchased the circuit breaker for a couple bucks!

The 15 minute runtime after towing will charge your battery but it is also for the transmission fluid and oil to get circulated again. If you add the battery line, you will still need to do the 15 minute runtime.