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Joined: Wed Jun 12, 2019 9:55 pm

AC Turns On during DC Charging

Fri Jun 14, 2019 11:29 pm

Ok some backstory, I took my 2017 FFE to Ford because the Serverly Limited Performance light kept coming on while charging. I suspected the TMS was not coming on an I noticed the AC would not blow cold air. Turns out Rodents chewed the wires on the wire harness. Anyways Ford fixed it but I had no juice on my way home so I stopped at a DC charging station for the first time. I figured Id wait inside the car (off) while charging and suddenly the AC starts blasting on cold air even with the car is off. I turned the car on, turned off the AC, and turned the car off again. A few mins later the AC turns on again but lower all on its own.

Is this normal operation for the TMS? I read all through the forum on how the TMS fans turn on to keep the battery cool but I didnt expect the inside cabin AC to turn on as well. Or is it possible Ford criss crossed a wire somehow within the wire harness fix and the AC is coming on rather than the TMS? Thoughts?

Level 1 and Level 2 charging has not shown the same results, only my first DC charging attempt so I am unsure if this is normal or not.

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Joined: Tue Feb 12, 2013 4:36 am
Location: Southeastern MI
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Re: AC Turns On during DC Charging

Sat Jun 15, 2019 2:32 am

Yeah someone mentioned that the AC comes on when DC fast charging. The car is doing everything it can to keep the batteries cool at that time.

I know when I've fast charged my Bolt and another Bolt that I've rented they both made a huge racket as just about every fan on the car comes on to keep things cool.

It makes sense: at the voltages and currents happening during a fast charge just about everything is going to warm up quickly (not to mention the battery).
2018 Cajun Red Chevy Bolt
2016 Magnetic C-Max Energi (lease returned)
2014 Sunset Escape
2014 Thor Axis (V-10)
2013 Focus Electric (lease returned Jan 2016 for the C-Max above)

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Joined: Thu Aug 15, 2019 8:17 am

Re: AC Turns On during DC Charging

Tue Sep 17, 2019 4:55 pm

I just noticed it today when I hooked it up for the first time to my home Level II charger. I heard the fans running and thought I left the car on. I opened the door to check and the dash lights were off. Now I am glad to know why.

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