Thermal management when not plugged in....?

We understand that the TMS operates only when the car is either plugged in or running. This presents an issue for those needing TMS but not able to plug in while parked.

Anyone know a reason not to simply leave the car switched on while parked? Wouldn't this address the issue? Obviously some battery capacity will be used, so this won't work in every case, but seems to me often it would

Someone studied TMS in the Volt and he found this worked OK even with Volt's smaller battery...during 7 hours in the hot Arizona sun only 30% of the Volt's SOC was consumed.

What I do to address the issue is remote start the car when it's parked in direct sunlight over 100F. It runs for about 10 minutes before shutting itself off. Did this a few times at about 2pm during long hot summer days. Doing so prevented the email notifications asking me to plug it in.

On hot days I keep it charged at 40% - 70%; seems like at over 80% charge the TMS wants to come on sooner and at lower temps (less than 100F ambient).

Haven't tried starting it up in-car, then leaving it on and walking away... will it let you do that? If so, maybe I'll try that this summer.

The horn hill honk if you leave it running, get out with the key and close the door (just one honk).

I haven't tried locking and walking away, just know about the horn honk from car washes.

Leave the key inside and walk away. You can lock and unlock using the mobile app, or possibly with the second key.

The bigger issue is whether doing this is worthwhile.


V-trav...it's really interesting and makes sense that it works that way...I didn't realize. Battery is most susceptible to degradation at high levels of charge. At lower levels, effect is minimized.

When the weather gets hotter I'll try to monitor the battery temp, see if it actually keeps it cooler. Right now I'm seeing in the high 90's which I don't love.

michael said:

Leave the key inside and walk away. You can lock and unlock using the mobile app

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Yes, but beware that the mobile app doesn't communicate directly with the car. The "unlock" command goes through the internet, is processed by Ford's servers, and the back to your car via its cellular data connection. So, good luck getting back in your car when the servers are having issues (which can be often), you phone has no internet connection, or the car is out of cellular range.

Something about leaving a car running (yeah I know it is just turned on) unattended for hours seems wrong. Everything in my brain says don't do that, it is dangerous. Seems like asking to have the car stolen.

But then again, that might be totally irrational with an electric car.

EVA said:

Something about leaving a car running (yeah I know it is just turned on) unattended for hours seems wrong. Everything in my brain says don't do that, it is dangerous. Seems like asking to have the car stolen.

But then again, that might be totally irrational with an electric car.

Click to expand...

Yes, same here, feels weird to leave it running.

But michael raises an interesting question and maybe we need to look at this as a new paradigm.

I'd be interested to hear feedback on Ford on what there recommendations are on this?

Even if it possible to do "safely", beware that the dash and MFT stay all lit up with the car is on. This might invite (eps. at might) somebody to notice your car and "get ideas" about messing with it.

This is also the reason I disable the charge ring lighting when charging in public (esp. at night). I leave it off. I want as few people noticing my car as possible.

You can definitely leave it running and walk away with the key. Did it several times inadvertently after we got the car. Its a bit disconcerting to come back to your car two hours later and find that its still on. Never crossed my mind that this was even possible, as the ActiveE shut down if you got out of the car, even if the key was in the ignition.

Car can be driven away without the key in this circumstance too. Tested it by having someone in the car climb into the drivers seat and drive away after I got out and left it running. Still need to test and see if someone can get in and drive away if you leave it running and don't lock it up.

The owner's manual does state that you can drive the car around without the key--you just can't restart it. Thus if your friend drives away with it they will be stuck as soon as they turn it off.

jmueller065 said:

The owner's manual does state that you can drive the car around without the key

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I find this a bit odd. Is this how all "keyless" ignitions work, or just Ford's?

But thinking about it, seems there could be a safety concern with a more "aggressive" system... if something went wrong with the "key detection" while driving, the car could suddenly shut off. So, I guess the alternative is: one turned on, stay on, even if the key goes away.

Contrary to what others have reported, my FFE does not honk if I leave it on and walk away with the key. Does yours?

Mine does.

twscrap said:

Still need to test and see if someone can get in and drive away if you leave it running and don't lock it up.

Click to expand...

If the green "ready to drive" icon on the dash is lit then yes, it will drive. As I'm sure you know, you can press the start button without your foot on the brake to put the car in accessory mode. This is presumably the mode you would leave it in for TMS. Unfortuantly as mentioned earlier the screens remain on and I'm sure other unneeded auxiliary systems would be running resulting in a quickly draining battery.

Why doesn't Ford give us the option to enable TMS when parked? Reeks of planned obsolescence to me. Why can't I maintain my very expensive battery to the best of my car's ability? My commute is short enough to have my car sit 20ft away from the sun and still have enough power to get home with AC blasting.

So I think we've agreed you CAN leave the thing running, and you CAN lock it. The real question is if we think it would be a worthwhile thing to do on a hot day?

I can tell you I once sat in my car with the air conditioner running for a hour and a half, nice and comfy. Would never have done that in an ICE with the engine running and burning gas.

WattsUp said:

Contrary to what others have reported, my FFE does not honk if I leave it on and walk away with the key. Does yours?

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This is also in the owner's manual: It is supposed to honk the horn when you close the door with the "engine running" if the key is not in the vehicle (mine does this).

jmueller065 said:

WattsUp said:

Contrary to what others have reported, my FFE does not honk if I leave it on and walk away with the key. Does yours?

Click to expand...

This is also in the owner's manual: It is supposed to honk the horn when you close the door with the "engine running" if the key is not in the vehicle (mine does this).

Click to expand...

Hmm, is that the same feature then? You're supposed to exit with the key and then close the door? Maybe I didn't do exactly that.

I just tried turning the car on and walking away with the key; no honk. But, I think I just did it through an open window.

Yeah it seems to take the door being closed to trigger the honk.

This is what will get mine to honk:

• With key in pocket
  Get in
  Close door
  Start car
  Open door
  Exit
  Close door
  *honk*

jmueller065 said:

Yeah it seems to take the door being closed to trigger the honk.

Click to expand...

I followed your steps and my FFE still did not honk. I walked about 50 feet away.

You mentioned that this feature is described in the owner's manual. I cannot seem to find it. I looked over every reference to "horn". (There is no reference to "honk", btw.)

Do you have the page number?

WattsUp - I think the honk was part of an update (if I recall from your posts, you haven't done that update).

My 2013 did not honk (and it was never updated). The 2014 does honk.

The accessory start only lasts about 20 minutes, the car shuts itself off after about that much time. I've sat in the car listening to the radio and had to repress the start button to keep listening.

EVA said:

WattsUp - I think the honk was part of an update (if I recall from your posts, you haven't done that update).

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As far as I know, I have all the updates. I finally had them done around New Years.

But, specifically, do you know which update addressed the "honk if left car on" behavior?

Also, was this the same update that should have ensured that the chime sounds when the door is opened but the ignition is on? My FFE now has that chime (and started doing it after I got the car back on after New Years). Before getting the updates, it would not chime if I opened the door with the ignition on. Now, it chimes exactly 5 times (and stops) if I open the door with the ignition on.

EVA said:

The accessory start only lasts about 20 minutes, the car shuts itself off after about that much time. I've sat in the car listening to the radio and had to repress the start button to keep listening.

Click to expand...

Actually, it seems to be 30 minutes. See page 46 of the 2013 manual.