Community Forums

kenj5 · 08-16-2019, 11:55 AM

Hi everyone. I'm about to start towing a Honda CRV behind my Gulfstream Tourmaster. I'll have the ignition switch of the Honda at 'accessory' position to allow the steering to unlock and move freely. Here's my concern. The CRV has a very small battery. Clearly, my intention would be to have all accessories with power switches turned off. That still leaves things powered with the ignition switch to accessory. On a multi hour tow, I'm concerned about having the Honda battery run down to the point it won't start. I have the Air Force One braking system installed in the Honda, which could require power from the battery. I'm contemplating running the power to the braking system directly to the battery positive with a fuse between the battery and the brake system - then install an on-off switch downstream of the battery positive terminal and tow with it turned off. Any comments about your experiences or my plans would by appreciated. Thanx in advance. :>)

**Lt Dan** · 08-16-2019, 01:33 PM

Leaving the key in accessory position will put a drain on the battery. The Air Force One will also help drain the battery. Your best bet is to install a battery charge line from the motor home to the CRV battery to keep it charged.

Mr_D · 08-16-2019, 01:43 PM

I did 2 things with the '14 CR-V I just traded for a Jeep Wrangler.
1. Larger battery and battery box from an Odyssey.
2. Charge line from MH to CR-V
Never a problem after that.

Gary RVRoamer · 08-16-2019, 01:58 PM

ACC in the CRV isn't much of a worry, but the AF1 adds a substantial load if you brake much. I'd add a 12vcharging line (or a Toad Charge device) just to be sure.

TOAD-CHARGE Dinghy Vehicle Battery Charger/Maintainer

MSHappyCampers · 08-16-2019, 02:19 PM

Hi ! Welcome to IRV2! We're sure glad you joined the gang!

Others gave you the same advice I would have. Just noticed you are kinda new on IRV2 and wanted to say hello! Have fun and keep her between the ditches!

Good luck, happy trails, and God bless!

kenj5 · 08-17-2019, 09:34 AM

First of all, Joe and Annette, thanx for the nice welcome - much appreciated! Thanx also to everyone who forwarded their very good ideas I hadn't considered. I'm wondering about 2 things:
1. If I was to replace the battery tray in the Honda, is that just a straight
'unbolt the old tray, and bolt in the new tray', or does the new Odyssey tray
require some fabrication or modification?
2. I'm wondering how to go about taking a charge line from the coach to
the Honda. I'm powered by a 450 hp Cummins, so tho I don't know the
output of my alternator, I'm guessing it's substantial and I'm guessing it
has a large diameter wire from the alternator to the chassis batteries.
- would I just run a charging wire from the chassis battery positive to the
Honda, or would I have to create a junction in the circuit from the
alternator wire to the chassis batteries and run it to the Honda?
- would that wire go through the same harness as my brake lights,
running lights and turn signals? I believe it's a 5 or 6 pin connector.
- maybe Demco sells a kit to facilitate a charge line??
Thanx in advance to you all for any further insight. .. Ken

Cat320 · 08-17-2019, 12:11 PM

I put an Odessey battery in my CRV. I did not use the Odessey battery tray, the battery fits, but it's tight..did not try to use a different tray, just discarded the OEM tray.

Peter M · 08-18-2019, 05:43 AM

Quote:

Originally Posted by kenj5

........

- would that wire go through the same harness as my brake lights,

running lights and turn signals? I believe it's a 5 or 6 pin connector.

Ken

Yes.

Most likely a 6 pin connector, you can use the center pin # 2 for toad charging.

https://www.roadmasterinc.com/pdf/85-5303.pdf

For safety reasons, Your braking system requires the power source from the toad battery. If not during a breakaway event the aux system would not stop the toad.

Wayne M · 08-18-2019, 09:26 AM

Kenj5,
I previously towed a Saturn Vue and now Lincoln MKX. I have had problems with both so I carried a battery charger that I could hook up to the pedestal or MH with Generator running and while I was disconnecting, 5 or so minutes later I could start the car. The mention of a charge line is very good advice. Do a search on "rv charge line" and you will see the many different companies that supply the equipment. Also, 7 pin connectors can vary so make sure the model you have has a 12v unused pin somewhere.

I still have not added a charge line, but it is next. In the meantime I recently experienced a weakened battery when I stopped at a CG. I very nice camper came by with a device that looked like this: Jump Start. I was surprised that this little 3/4 inch thick, 3 inch wide by 6 inches long little thing would start a car, but it did. I now have it stowed in the TOAD.

Yes, accessory position will cause a slight drain on the battery. A more problematic drain is any braking system that activates the car's brake lights especially in hilly country when braking is constantly on and off. I have not had a problem on level terrain. I also use AF1.

Happy trails.

Carlos Marti · 08-18-2019, 09:35 AM

Au contraire,. The AF1 uses zero battery power. The breakaway will use battery power if there's a breakaway. Lights are powered by the coach. Vacuum for the toad's power brakes is produced by an air powered venturi. No moving parts other than the actuator on the brake pedal.

Quote:

Originally Posted by Gary RVRoamer

ACC in the CRV isn't much of a worry, but the AF1 adds a substantial load if you brake much. I'd add a 12vcharging line (or a Toad Charge device) just to be sure.

TOAD-CHARGE Dinghy Vehicle Battery Charger/Maintainer

Ljwt330 · 08-18-2019, 09:48 AM

Regarding a charge line from the MH to the CRV.

If you plan on using the existing cord from RV plug to the toad, you will be limited by the size of the wire inside the cord as to how many amps and the size of fuses you will need. A simple charge wire from the MH positive to the umbilical cord pin will suffice, with a fuse installed as close to the battery as practical. On the CRV side, same set up with another fuse close to the battery. The gauge of wire you use from each battery will be your choice, but the fuses must be sized to protect the smallest gauge wire in the circuit--probably the wire in the umbilical cord.

Wayne M · 08-18-2019, 01:57 PM

Quote:

Originally Posted by Carlos Marti

Au contraire,. The AF1 uses zero battery power. The breakaway will use battery power if there's a breakaway. Lights are powered by the coach. Vacuum for the toad's power brakes is produced by an air powered venturi. No moving parts other than the actuator on the brake pedal.

What happens to the brake lights when the brake pedal is depressed?

Carlos Marti · 08-19-2019, 07:45 AM

Quote:

Originally Posted by Wayne M

What happens to the brake lights when the brake pedal is depressed?

As I said brake lights are powered by the coach. In my situation, I have the toad battery disconnected, and a separate wire to the battery for the breakaway.

kenj5 · 08-19-2019, 09:13 AM

A big thank you to all of you who have offered great information to my query about power drain on my Honda battery equipped with the Air Force One braking system.
As there were some discrepancies in the answers that came back to me, I elected to check in with the manufacturer to get clarification. For those who may be interested, here's their reply:
"Ken,
The Air Force One will draw some power each time the LED indicator light needs to power up from the braking system being activated. But we’re talking milliamps that this draws, so for it to drain your battery by itself the LED light would have to be on 24/7 & even then it’d take upwards of 2-3 weeks for it drain the battery. This means you’d tow your CRV without ever starting/driving it & the LED would need to be on the whole time."