Hybrid towing

We have 2010 Tiffin Phaeton and have purchased 2013 Ford C-Max Hybrid to tow. What type supplemental brake system are you using? We are using a 9160 Brake Master by Road Master and have experienced a little problem on our first attempt at towing. I'd like to know more if anyone is using similar supplemental brake system. Thanks!

Thank you for the info. I was able to take ground and +12 off the six pin connector and connect to the battery. Traveled over 6 hours in one day without any mishap. Have traveled several more days, all running perfectly. Just a side note, it would be nice if dealer/installers would recommend this when installing equipment. They already have everything apart and its only two more wires.

Happy trails to all who have responded to my inquery.

Thanks all for the great info.

I believe I'll be looking to buy a C-Max in the next couple of weeks. And you've given me assurance that this is the right car.

Just before we started motorhoming, I bought a Prius. Loved it. But when we started motorhoming, we had the Prius and a Subaru Forester. The Prius went away. Now that its time to replace the Forester (its a 2000) I've been concerned that there wasn't anything really good to replace it with! But now I see I was wrong. The C-Max appears to be a great TOAD.

- stp

EB Expedition wrote:
It was mentioned in a couple of recent replies that a charge line was installed. I have a six pin connector at the cmax, but only using four pins. I believe the other two are for ground and +12v. Can you please explain how you connected your charge line to your tow vehicles? Did you hardwire directly with 12volts from the rv six pin connector to the battery positive and ground.

Check the wiring, but you should already have ground wired in. That would be one of the 4 pins you are already using.

Sooo, really all you should have to do is use one of the extra pins on your six pin connector to run a +12V line to your battery. Run a wire from the + terminal of your battery to one of those extra pins on the six pin connector. Preferably 10 gauge, and you definitely need to put a fuse on it, right near where it connects to that + lug under the hood.

Even though you probably already have ground wired in, you may want to look at beefing up the ground wire that goes from your 6 pin connector on your Cmax to where ever it connects to the ground. Reason being, you now could potentially be pushing a bit more current through there to keeping the battery charged up.

Then, on the MH side, you'll have to find a fused 12V wire to wire to that pin. If your MH came with a 7 pin connector (most do), one of them will be a 12V line, and you should be able to use that. Thats what I did, made it pretty simple.

RViBrake just came out with a cool product, their Toad battery charger that makes wiring a charge line a bit more simple. This device includes most of the wiring you'll need for this, and protects it with a fuse and diode so you don't have to fool with installing an inline fuse. Price is pretty reasonable too, at $50. I may well add this to mine, one of these days.

On my cmax the battery is buried in the back and I only have a positive connector under the hood and common ground lug post near the battery positive terminal used for jump starting the car.

My Fusion Hybrid has exact same thing - battery in back, positive and ground lug under the hood for jump starting. Those lugs are what I wired our charge line to, it worked great. Made it very easy to run the wires to the connector on the front.

Anyway, hope this helps. I would definitely try to get this done before your next trip, as you don't want to deplete your starting battery any more than is absolutely necessary, or like mentioned before, you'll get to replace it sooner than you want to.

We towed our cmax hybrid on a long trip for the first time yesterday, and yes, the battery did die after about 4-5 hours. It was mentioned in a couple of recent replies that a charge line was installed. I have a six pin connector at the cmax, but only using four pins. I believe the other two are for ground and +12v. Can you please explain how you connected your charge line to your tow vehicles? Did you hardwire directly with 12volts from the rv six pin connector to the battery positive and ground. On my cmax the battery is buried in the back and I only have a positive connector under the hood and common ground lug post near the battery positive terminal used for jump starting the car.

With my now properly connected charge line I have towed for over five hours with no problem. The car is a 2013 C Max. Just be sure the charge line is attached to the battery terminal. Mine was originally attached to the wrong terminal.

EB Expedition wrote:
We just upgraded to a new Class A motorhome and traded our Expedition in for the 2013 Ford CMax Hybrid. We are using Blue Ox tow bar and RViBrake2 for the CMax. Connect the CMax to the tow bar.

The CMax has the push button start. To setup the car for towing: do not press the brake pedal when pushing the start button (this will put the car in Acc. mode). Ensure that the parking brake is set, then press the brake pedal and shift into Neutral and release the parking brake. Follow directions for the brake controller. After completion verify that the brake lights on the CMax are not lit before traveling. I failed to do this and fried two tires (not cheap to replace) with the brakes being applied. Also note that the CMax will go into standby mode after approximately 1 hour, turning off the 12V outlet in the center console. I had to run a dedicated 12v adapter from the battery to use with the RViBrake2. We make it a habit not to drive more that 4-5 hours each day, and we haven't had our new RV for long, so we haven't had an issue with a dead battery as of yet. If this happens then I may consider putting in a 12v charger or direct 12v from the RV. For safety, as with any tow vehicle (toad or TT)always check everything periodically while on the road.

Me thinks, although you've not had a problem yet, you're going to soon be running a charge line (direct 12V line from MH to your Cmax's battery). Or, wishing you had.

If you have a clip-on ammeter, do this one time: Go through all the motions/procedure you mentioned above for setting it up to flat tow. Tranny in neutral, etc. Then, clip your ammeter on one of the wires going to the battery, see what kind of amp draw you have on the battery. Have someone engage the RVibrake a few times to make it engage the brakes, and watch that ammeter.

YMMV, but I found with our Ford Fusion hybrid, there was a constant 3 amp draw on the battery all the time when it was in 'flat tow' mode (tranny in neutral, ignition in ACC position). Have spoke with other hybrid owners that found the same thing as well (both Cmax and Fusion hybrid owners). And this is before even considering the amperage your RViBrake system uses.

And, remember, power braking assist stays on all the time with these hybrids, so every 2nd or 3rd time your RViBrake engages the brakes, the vehicle's brake boost vacuum motor will come on also and use battery power. And, as alluded to earlier, there is probably other systems that may cycle on and off from time to time when towing these hybrids, that would take even more from the battery.

Our first trip towing the Fusion, I did not have a charge line installed. 'Twas about a 4 hour drive, and that was all it took to run battery almost completely dead - it couldnt even operate the power locks. That was all it took for me. I installed the charge line right after that. We've never had to worry about the Fusion's battery again since then, no matter how many hours we're on the road towing.

Remember also, that starting batteries are not meant for deep cycle use, which is what you're using them for in this case if you don't run a charge line. Using a starting battery this way will shorten its life span significantly. A charge line is much, much cheaper than a new 12V battery. :)

We just upgraded to a new Class A motorhome and traded our Expedition in for the 2013 Ford CMax Hybrid. We are using Blue Ox tow bar and RViBrake2 for the CMax. Connect the CMax to the tow bar.

The CMax has the push button start. To setup the car for towing: do not press the brake pedal when pushing the start button (this will put the car in Acc. mode). Ensure that the parking brake is set, then press the brake pedal and shift into Neutral and release the parking brake. Follow directions for the brake controller. After completion verify that the brake lights on the CMax are not lit before traveling. I failed to do this and fried two tires (not cheap to replace) with the brakes being applied. Also note that the CMax will go into standby mode after approximately 1 hour, turning off the 12V outlet in the center console. I had to run a dedicated 12v adapter from the battery to use with the RViBrake2. We make it a habit not to drive more that 4-5 hours each day, and we haven't had our new RV for long, so we haven't had an issue with a dead battery as of yet. If this happens then I may consider putting in a 12v charger or direct 12v from the RV. For safety, as with any tow vehicle (toad or TT)always check everything periodically while on the road.

After playing around out in the COLD and checking where acc is, it is evident that I have been in that "gray" area of switch selection. If some of you believe that the transmission and electronics are possibly cooled by having the switch in the acc position then that is what I am going to try on our trip down south for the winter...:) Safe travels!

willald wrote:
These hybrid drivetrains are pretty complicated. There are several pieces to it that are powered electrically, that in a conventional drivetrain are powered mechanically, by the crankshaft. Sure hope you aren't turning one or two electrically powered components off thats going to cause some issues later on. Specifically, I really hope there's not an electrically powered transmission lube/cooling pump somewhere, that you are turning off and Ford intends to be on when towing.

There is a pump for cooling the transaxle and electronics, at least in the 2006 Escape Hybrid. I doubt that there is much heat being generated while towing, but you are absolutely right in that it's smart money to follow the towing directions to the letter. These hybrids are a great thing and work well, but there are several systems that control engine and battery temperature that are critical to the vehicle running right.