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S100D Air Conditioner Cuts out on Humid Days?

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Hi!

I had my Model S since November now and it runs great! I am experiencing an interesting problem though - on hot (esp humid) days, the air conditioner will stop pumping cool air for about 1-2 minutes in the cabin. This causes the temperature to spike very quickly. I even have this plotted on TeslaFi (see the dark red line)

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At approx 11:47 am today, I jumped on a freeway onramp and roughly at the same time the air conditioner stopped blowing cold air. I bumped the temperature from 68 down to LO in hopes that would fix it, however, nothing changes and the car gets warmer for another minute or so to a peak temperature of 84 degrees. After about 90s, the air conditioner abruptly turns back on and the car is cool again. The fan runs the entire time, just the temperature of the air is different. The air seems to be being pumped directly from the outside - it is noticeably more humid and warm compared to air that would otherwise be air-conditioned.

This seems to happen only on hot days, and only whenever I accelerate hard the first time of the drive. I'm not getting any error codes and service said this was normal when they looked at my logs (which is beyond me as to how this is acceptable in any car, let alone a higher-end car like the Model S) Service claimed that if the air conditioner is not set to LO it may do this to warm the car back up to the expected temperature, but with my temperature being 68 and the actual temperature being above that, I'm not sure why it would consider doing that, especially if it just cools back down to the original temperature shortly after. I also debunked this theory by setting my car to LO and then accelerating hard - the car still does the same thing.

Has anyone experienced this before? Is this normal? I'm not sure if I should accept this as a normal known issue or if this is something that is repairable. If it is repairable, I will need to go back to service to insist they look at it (which is something I absolute hate doing :p)

Cheers!
Andrew
 
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I think we had our A/C ice up a week ago on a long trip. It was out for maybe an hour, slightly cool air and low airflow. Worked again after the next Supercharger. Turning it off for a while would probably work best to de-ice if it's not doing it itself. Haven't had this problem before, and have never seen so many complaints on TMC, so maybe something a fairly recent firmware update screwed up.
 
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Definitely check that louvers are opening properly, and report the issue.

Battery cooling has priority over AC output. Strong demands of battery in extreme heat conditions can cause short periods where coolant flow is minimized for cabin. Should be for minutes, max, though I thought.

There might be a change in the algorithm that reduced max battery temp, as hot batteries have significantly shorter lifespan.

Edit: just looked at TeslaFi graph posted. 90 outside VS 74 inside at 70 mph... that shouldn’t be an issue to manage. Get it checked

Here’s a TeslaFi log from mine from yesterday... just fine. FW: 2018.26 3bbd9fd
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I have the exact same issue on my Sep 2017 S75D, Tesla downloaded the logs and told me it was a known issues. They have a new part (sorry no more details) that fixes the cutouts but it’s backordered.

Interesting. Brought my 100D into the SC a few weeks ago for this very same issue and was told it would just require a software update that wasn't out yet. Looks like I need to get another appointment at the SC since this is still happening to me and see what the answer is this time.
 
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Canadian S100D June 2017

I had this happen in a hot and humid day in 2017. No cold air was blowing out of the AC for 30 minutes, slow stop and go traffic on a hot and humid day. Decreasing the temp to LO and or increasing fan did nothing, still hot and humid air from vents.

Problem went away after 30 minutes and it blew cold air again. Never seen it again so far.

Maybe the evaporator iced up?
 
We gave had numerous issues with the AC on our current roadtrip [CA to CO). The service center could not find any issues before we departed, but the issue crops up every 800 miles or so.

I hit the "reset auto settings" and that worked a couple times. Clicking on outside air and then back to recirculating seemed to fix it a few times as well. Will definitely be going back to a service center if it fails on the next leg of our trip from CO to Los Angeles.
 
I know exactly what you are seeing. Had this happen to me as well.

I have been driving a lot in very hot weather recently. Sometimes very extreme heat. Up to 116 F. I noticed these moments of the AC seeming to cut out sometimes. It not actually cutting out. It is just shifting things around! At these extreme temperatures the AC keeps the air on recirculating. This is much more efficient. Every once in a while it has to let fresh air in and then it suddenly has to cool the hot outside air down to cabin temperature. The AC usually can't do that fully when it is very hot outside and for a few minutes it feels like the AC isn't working properly. Once it switches back to recirculating, the air is feeling much cooler again.

Another issue is that driving at very high temperatures, sometimes the battery gets very hot and the car uses the AC system to cool it. That takes up some of the cooling from the cabin away. Sometimes the car even shows a message that AC power is reduced due to battery system cooling.

I have had both happen to me several times over the past 6k miles.
 
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