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Refresh Models S HVAC in Auto Mode doing odd things

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Well-Known Member
Aug 27, 2018
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Is this a software issue or sensor issue or what?

I have it in Auto Mode, Rear is on for the Dogs, And I have Recirculate on.

I had it set to like 78 with it in the 90's out.

Driving along for like an hour and suddenly it starts getting warm. Cool air still flowing to the back.

Very little air coming out of the dash.

I nudge the temp down 1 degree, no change, I nudge again, no change, then down to like 73.

Everything starts cooling again, now it's too cold. Turn it back up to 78 and it's good for an hour or so until it does it again.

I don't know if the sun changed angle and threw sensors off or what.

I really liked the Auto in my Raven X that I didn't have to mess with much. But if I recall if I hit recirculate it would take it out of Auto. Not sure if that later changed with software.

It might work better in manual, but I grew accustomed to Auto over time in the X.

When it was 80 out the past few weeks it behaved similar in that I'd have it on 73 and it would be to hot, and I'd have it on 72 and it would be to cool.
When it was in the 90's it kind of did the same thing but way more extreme. 73 too cold, and stayed to cold up to setting it 78 or 79.
But once it thinks I need less cooling lowering it 1 degree was not enough, I had to lower it like 5 degrees.

It had plenty of capacity if I lowered it enough.

Now I did have two small dogs on the back seat and the seat belt lights were going off and on. But the rear was more consistent then the from.

I think it was turning down the front blower but left the floor running. And that quickly feels hot on a hot day. It's not until I lowered it enough that it would kick the front fan back on.
 
My 2020 Raven also does this, and I think it is the car prioritizing battery cooling over passenger comfort. I have the same issue in Winter with heating. You just have to kick her down a few degrees and maybe up the fan to keep both you and the battery comfortable. Auto doesn't seem to work with more extreme temperatures without adjusting things.
 
My 2020 Raven also does this, and I think it is the car prioritizing battery cooling over passenger comfort. I have the same issue in Winter with heating. You just have to kick her down a few degrees and maybe up the fan to keep both you and the battery comfortable. Auto doesn't seem to work with more extreme temperatures without adjusting things.
I was thinking that too but ruled that out. Also never had the issue on my Raven X.

It will give me all the cooling I want if I nudge it down. And I suspect if I had it in manual mode it won't do this.

If battery really needed more cooling it would not give more cooling just because I say I'm hotter.

It just decides to redirect the fans out of the blue in Auto.

I'll try Manual mode on the next trip and see what it does.
 
I also think the Auto climate settings are prioritizing economy, so it does not adjust as fast, if at all. Like we both state, if you crank it down, it cools. Perhaps it hopes you won't bother forcing the extra cooling, helping to increase the total miles to empty.
 
I also think the Auto climate settings are prioritizing economy, so it does not adjust as fast, if at all. Like we both state, if you crank it down, it cools. Perhaps it hopes you won't bother forcing the extra cooling, helping to increase the total miles to empty.
It makes no sense. For the first hour I nudge it up a degree it's warmer, nudge it down it's cooler. Fan stays steady. Could run like that for an hour.
And out of the blue it just shuts the front fans off. I nudge it down a LOT, fans come on, I put it back where it was and it's good for an hour again.

Maybe it thinks turning fans off will save power and it's completely wrong it can stay even close to the same comfort. Not sure if it turns cooling down too. It's hard to tell because the fan is on 1 or zero and it's hard to reach my feet. The fan in back stays going. It feels so much better I assume it's full cool, but it might not be either. But it feels so much better than the front because at least the air is moving.

I'll do the same trip Friday in the same temps and I'll leave it on manual and see what it does.