Flat Towing c-max battery always dies

[marciamooma]

My C-max always has a dead battery after only 1-2 hrs. Anyone else have this problem. I flat tow it and it's a hybrid 2004

Thanks
Marcia

 

[BoomerD]

Not yet...I just bought a C-Max to use as a toad... 

How are you setting the car up to tow? 

The owner's manual says:

If you tow your vehicle with all four wheels on the ground:
? Tow only in the forward direction.
? Release the parking brake.
? Place the transmission in position N.
? Place the ignition in the accessory mode. See the Starting and
Stopping the Engine chapter.
? Do not exceed 70 mph (113 km/h).
? Place the transmission in position P, start the engine and allow it to
run for one minute at the beginning of each day (you may need to
press the accelerator pedal in order to start the engine). After
allowing the engine to run, place the transmission back into position
N and the ignition in the accessory position

Is it possible that in the accessory position, you're powering something like AC or ???

 

[John From Detroit]

There are several possible issues.

First: The battery may be nearing "end of life" when this happens.. What you describe happens.

Second, What aux brake system do you have, Many including all the "System in a box" systems suck power from the towed's battery.

Third: again is the brake system properly adjusted,, Brake lights can suck a LOT of power if not LED. around 20-25 watts per lamp.  or about 2 amps per lamp (Ouch).

Other loads from the Accessory position of switch (See above replies)

What can be done about it?

Often there is a fuse or two you can switch (Either pull the fuse when towing or add a switch).

Or, back to aux brakes, US Gear Unified Brake Decelerator system INCLUDES a "Towed Charge" line that ties your towed to your chassis electrical system for charging...

Or, there is a product called Towed Charge or Toad Charge (not sure if they punned or not)  Same idea.

 

[marciamooma]

Thanks guys for the reply's to my post. I have a push button start 2014 C-Max Hybrid, so I can't put it in acc.  I do put it in Neutral and I make sure all things, ex. radio, lights AC are off. It would still run the battery down. I have no extra braking system installed. I had the battery's checked at the dealer also and they said they were fine. Still always after 2 hours of flat towing the battery would be dead and I would have to put a charger on it to start.

Yesterday I had the umbilical cord that runs from the MH to the car switched from a 4 hole on the car end to a six hole, so now it has a hot lead running direct from the MH to the car which should eliminate the problem.

Just a future heads up to anyone flat towing a C-Max Hybrid....beware when setting up your tow package always use a 6 or 7 hole connection on the car end to alleviate the problem.  The guy at the garage said it was the second C-Max he had this week, same problem.

 

[BoomerD]

Thanks guys for the reply's to my post. I have a push button start 2014 C-Max Hybrid, so I can't put it in acc.  I do put it in Neutral and I make sure all things, ex. radio, lights AC are off. It would still run the battery down. I have no extra braking system installed. I had the battery's checked at the dealer also and they said they were fine. Still always after 2 hours of flat towing the battery would be dead and I would have to put a charger on it to start.

Yesterday I had the umbilical cord that runs from the MH to the car switched from a 4 hole on the car end to a six hole, so now it has a hot lead running direct from the MH to the car which should eliminate the problem.

Just a future heads up to anyone flat towing a C-Max Hybrid....beware when setting up your tow package always use a 6 or 7 hole connection on the car end to alleviate the problem.  The guy at the garage said it was the second C-Max he had this week, same problem.

Actually, with the push button models, IIRC, (and that's what we have) if you push the start button with your foot OFF the brake, it should be in ACC mode. (not sure how long it will stay in that mode, especially if you don't leave the key fob in the car with it)
Depending on where you tow, you probably HAVE to have a braking system by law. IIRC, there's only about 7-8 states that don't require some kind of brakes on towed vehicles.
http://www.brakebuddy.com/towing-laws

PLUS, that extra 3500 or so lbs. can really tax your coach brakes. (which are often barely enough to stop the coach by itself)

 

[Gary RV_Wizard]

I have a push button start 2014 C-Max Hybrid, so I can't put it in acc.  I do put it in Neutral and I make sure all things, ex. radio, lights AC are off. It would still run the battery down.

Are you following the specific instructions for "Recreational Towing" found in your 2014 C-Max owner manual? The hybrid model is different than the AWD and FWD models. And the "Starting & Stopping" the engine sections will explain how to put the ignition in the Accessory mode rather than ON.

 

[BoomerD]

My apologies. I don't know how I missed the "2004 C-Max" part of the original post. I didn't realize Ford made this car that far back...I thought 2013 was the first year in the USA.

Looks like I was right...

Ford introduced the C-Max in the United States as its first hybrid-only line of vehicles, which includes the C-Max Hybrid, released in September 2012, and the C-Max Energi plug-in hybrid, launched in October 2012. Although C-Max was initially available only in Europe, the first generation was partially available in New Zealand. With the introduction of the new large MPVs S-Max and Galaxy, the C-Max is the mid-sized multi-purpose vehicle in Ford's lineup, above the B-Max.

Unfortunately, I can't locate the actual manual for this car without knowing where it was first sold.

 

[Gary RV_Wizard]

I have a push button start 2014 C-Max Hybrid, so I can't put it in acc.

Her later message identifies it as a 2014 hybrid

 

[BoomerD]

Her later message identifies it as a 2014 hybrid

Sheesh...I REALLY need new glasses... :

In which case, the info I originally posted about towing procedures was ALMOST correct. (I think I posted the procedures for a 2013, not a '14)

http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2014-CMAX-Owner-Manual-version-1_OM_EN_11_2013.pdf

The keyless starting system has three
modes:
? Off: Turns the ignition off.
? Without applying the brake pedal,
press and release the button once
when the ignition is in the on mode,
or when the vehicle is on but not
moving.
? On: All electrical circuits are
operational and the warning lamps and
indicators illuminate.
? Without applying the brake pedal,
press and release the button once.
? Start: Starts the vehicle. The engine
may not start when the vehicle starts.
? Press the brake pedal, and then
press the button until the vehicle
turns on

Recreational Towing
Note: Put your climate control system in
recirculated air mode to prevent exhaust
fumes from entering the vehicle. See
Climate Control (page 105).
Follow these guidelines if you have a need
for recreational (RV) towing. An example
of recreational towing would be towing
your vehicle behind a motorhome. We
designed these guidelines to prevent
damage to your transmission.
You can tow your vehicle with all four
wheels on the ground or with the front
wheels off the ground by using a tow dolly.
If you are using a tow dolly follow the
instructions specified by the equipment
provider.
If you tow your vehicle with all four wheels
on the ground:
? Tow only in the forward direction.
? Release the parking brake.
? Place the transmission in position N.
? Place the ignition in the off position.
See Starting and Stopping the
Engine (page 124).
? Do not exceed 70 mph (113 km/h).
? Place the transmission in position P,
start the vehicle and allow it to run for
one minute at the beginning of each
day (you may need to press the
accelerator pedal in order to start the
vehicle). After allowing the vehicle to
run, place the transmission back into
position N and the ignition in the
accessory position.

(note that in the first section of the towing procedures, it says "Place the ignition in the off position" but in the later part it says "place the transmission back into
position N and the ignition in the accessory position."

That's a discrepancy that should be addressed.  Off or acc?

 

[wilanddij]

Hi, I just joined the RV Forum, so maybe this topic has already been handled, but thought I'd put my $.02 in anyway. I tow a 2014 C-Max with button start, and solved the battery drain problem by adding a 12V charge line from the Motorhome to the battery. The line needs to be fused to avoid any overdraw problems, but I have never had a problem with it.

 

[av8tor]

I will be towing my 2013 CMax hybrid.  Can anyone tell me if the miles on the odometer of the car, changes while towing? 

 

[JoelP]

I am thinking of buying a 2014 or 2015 C Max Hybrid to tow behind our RV.  On a separate forum there was a discussion of severe vibration after making a left turn over a bump with a C Max Hybrid.  It said that it persists until one stops and starts again.  Has anyone else with a CMAX hybrid experienced this effect. Ford seemed to acknowledge the effect.  One response to that post said it could be overcome by misadjusting the castor 1.5 deg inward, but at the expense of tire wear. Is it possible that this is dependent upon the choice of tow bar?

 

[Alfa38User]

I will be towing my 2013 CMax hybrid.  Can anyone tell me if the miles on the odometer of the car, changes while towing?

On the modern electronic odometers, the miles do not register while towing. Reason? They, nor the engine computer are not usually powered on.

The old mechanical ones, where a cable came from the transmission directly to the odometer, usually did register the miles.

 

[JoelP]

Now I have purchased a 2016 CMAX Energi hybrid and have had a shop do the towbar install for my Roadmaster Sterling.  I had a 7 pin connector and asked them to please provide a trickle charge line.  It hooks up easily and tows beautifully, but I am a bit confused on not taxing the battery.  I followed the recommendation to turn off the radio etc, put it in recirc air started the engine in P and switched to N.  Then I pushed the button to stop the engine and pushed once to start it in the accessory mode, but still the display was powered and heaven knows what else.  I have yet to take it on a long enough drive to see if the battery is OK.

1.  For those with success on this configuration did I do the procedure right?  Or should the CMax simply be turned off?  Some people recommend that. My concern is that if it is Off it will not have power steering, or power brakes.  Aren't those necessary when towing?
2.  Can't the steering wheel lock up if it is in the Off state, or does that only apply to older vehicles?

Thanks for any input for others towing CMAx or a good knowledge of this vehicle.

 

[JoelP]

I figured this issue out recently and thought I would post this for those who might run into a similar issue.  The installer for my baseplate also put a Pollak brand connector where the center pin was used to trickle charge the battery of the CMax.  The housing of the connector is metal and has a little protrusion in the center of the spring sealing lid that can occasional touch that center pin. When it does, it can drain the current from the battery. I put a small plug of rubber pad into the connector and it solved the issue. I chose to not file down the protrusion on the connector since it serves to keep the matching connector from vibrating loose.