Strange regen/charging issue

[Splatt]

model 3 LR. 2018 vintage. 76000 miles.
Currently on a 4 day road trip from Phoenix to Vegas and Anaheim. Started this morning from home. Charged in Wickenburg at what seemed like a good rate but wasn’t really paying attention. Next stop was the 250kw staion at White Hills north of Kingman. Arrived at about 7% soc. Started at 80kw and slowly decreased. When it had dropped to 60kw switched stalls with no change. Ambient was about 102F. Upon departing this station noticed several regen dots (soc was about 35%). As continued driving more dots appeared until regen was completely gone. Stopped at charger in Henderson and got 0kw. No error message. Charging screen looked normal otherwise. Scroll wheel reboot had no effect. Called roadside and they saw nothing wrong with tha car or charger. After about 15 minutes car started charging slowly (10kw) and eventually increased to about 40kw. On departure had about 75% regen. This slowly went to 0 regen.
Feels like a thermal issue. The large front fan is working. I wonder about the battery coolant system. But I’d think they would have seen that on telemetry.
has anyone had a similar issue? I’m a bit hesitant to continue to Anaheim tomorrow but would probably have to stay in Vegas until sometime next week to get a service appt.

 

[puckpurnell]

So sorry to hear about your troubles. Y I K E S ! Good luck heading west.

 

[Splatt]

Update
Got to our destination in vegas. Supercharged at Tivoli. Charging started at a decent rate and quickly dropped to about 120mph. Plugged into a 38A destination charger for the night and it charged just fine in the expected amount of time. Topped off to 100% this morning and headed to Anaheim. Stopped at chargers in Baker. Same issue. Added about 70 total miles. Stopped in Hesperia (soc about 45%) and got 900mph for about 10 seconds then rapidly dropped to 45kw. Added enough to get to our destination. Regen after this charge was limited by about 25% but all regen was available after about 20 miles. 10-15 degress cooler ambient than when we had 0 charging ability yesterday.
has anyone had issues like this?

 

[splatt0]

Update:
Made in home to Phx from LA yesterday. Stopped at 4 chargers en-route. Stayed at each charger long enough to get to the next. Charging rate quickly dropped to 20-40KW at each stop (better in CA where it was cooler, worse in Quartzite where it was about 107). Had limited or no regen for many miles after most stops.
After we got home, I started charging (Tesla wall charger). The very loud cooling fan stayed on for at least 6 hours but it charged fine.
Have a service appt on Aug 11 (was the next available slot).
Still hoping someone chimes in with a similar issue so I can give Tesla some ideas on what to look at (I'm well out of warranty). A bit concerned since they did not see any issues remotely.

 

[GtiMart]

Could you be out of glycol in the cooling system? The battery would heat up too much and would refuse to charge/regen?
Or maybe the pump doesn't work? When you are parked at home and wake the car up, do you hear a small electric pump working? Assuming the fan isn't running as its noise would cover the pump sound...

 

[splatt0]

GtiMart,
Thanks. I suspect something in this area. I'll listen for the pump sound. I'd think a pump failure or hot battery would have triggered some sort of message.

 

[Splatt]

Gtimart,
You were right.
the next available service appointment was 12 days out. Then they kept my car for five days before looking at it (they did cover a rental). I had to pre-approve the replacement of the superbottle for $600. When they got to my car, the service tech called me to get more info and said the coolant was low which could cause those issues. Total cost was $84. Supercharging seems to now be normal.
No coolant leak was found. Not sure how it could have escaped.