So "E-Heat" doesn't work in "Accessory Mode"?

4TangledKites

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Not a huge deal, I can always fully start the car, but I found it odd that E-Heat doesn't warm the cabin in Accessory Mode even though the fan motor blows. That's more ICE-like than I expected.

I discovered this on a chilly morning last week. Sitting in the parking lot while my kid was at the dentist. Cold air blowing out of the vents even when I jacked up the temperature. Surprised me.
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Not a huge deal, I can always fully start the car, but I found it odd that E-Heat doesn't warm the cabin in Accessory Mode even though the fan motor blows. That's more ICE-like than I expected.

I discovered this on a chilly morning last week. Sitting in the parking lot while my kid was at the dentist. Cold air blowing out of the vents even when I jacked up the temperature. Surprised me.
I believe the same is true for A/C. I suppose the idea is the HVB is isolated for safety while in Accessory Mode. But if that were the case, then how does the LVB get charged? Makes me curious to look at the wiring diagrams and see if there are special provisions to power the converter whole in accessory mode.
?
 

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I haven't really found a reason to ever use Accessory mode instead of just staring the car since there's no engine running either way.
Same here.
Maybe just to play the radio I guess?
 

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Not a huge deal, I can always fully start the car, but I found it odd that E-Heat doesn't warm the cabin in Accessory Mode even though the fan motor blows. That's more ICE-like than I expected.

I discovered this on a chilly morning last week. Sitting in the parking lot while my kid was at the dentist. Cold air blowing out of the vents even when I jacked up the temperature. Surprised me.
Best to start the car. If you leave it Accessory Mode to long you will have a dead 12 volt battery and the car wont start.
 


Sam2084

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I didn’t even know the Mach E had an accessory mode. It honestly makes no sense.
 

DK922

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Why use accessory mode? Trying to save on gas? ?
 

Hoff

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If I had to guess, it exists to allow access to certain components on the low voltage side in the event you drain the HVB all the way down or there is another major fault on the HVB side. Also, it could just be a legacy engineering holdover from when Ford was initially designing their first EV.

As to functionally, I doubt its a hard module, and is likely a logic gate in the electrical systems' bus controller that checks which mode you put it in, though there are likely separate physical buses for the LVDC and HVDC components.
 

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If I had to guess, it exists to allow access to certain components on the low voltage side in the event you drain the HVB all the way down or there is another major fault on the HVB side. Also, it could just be a legacy engineering holdover from when Ford was initially designing their first EV.

As to functionally, I doubt its a hard module, and is likely a logic gate in the electrical systems' bus controller that checks which mode you put it in, though there are likely separate physical buses for the LVDC and HVDC components.
I don’t like it not working as I can’t start the car while sitting at a fast charger and if it’s cold I would like to warm up. Kind of a no brained!
 

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I don’t like it not working as I can’t start the car while sitting at a fast charger and if it’s cold I would like to warm up. Kind of a no brained!
You should be able to start the car while charging. Depress the brake pedal and press the button. Car should start with full climate control functions. It won't drive of course but the heat should work.
 

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I thought the only thing accessory mode was used for is to reset the trip computer: LOL
 

nvabill

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nvabill

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You should be able to start the car while charging. Depress the brake pedal and press the button. Car should start with full climate control functions. It won't drive of course but the heat should work.
Ok, need to try it again, it told me something and when I tried I didn’t think it started, guess I was wrong.
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