mysterious hvac behavior when parked. Car is hot but HVAC is "off"

[polyphase]

So I parked at the airport for 4 days with 250 miles left in battery. when I got back there were 135 miles left. Sentry mode was on so big drain...I guess. But the strange thing is, outside temps were 40-50 degrees the whole time but the cabin temp was 80 deg F. when I returned! HVAC was "off" and no preconditioning schedule was active. The last thermostat setting was 70 deg.

Right now the car is in a public garage charging with 110V. Temp in the garage is 71 but, again, the cabin temp is 80 deg.

What is happening? Thanks.

 

[ucmndd]

Cars are greenhouses.

Running sentry continuously keeps the autopilot computer and MCU on all the time. Those computers are in the cabin and produce heat.

 

[phxazcraig]

So I parked at the airport for 4 days with 250 miles left in battery. when I got back there were 135 miles left. Sentry mode was on so big drain...I guess. But the strange thing is, outside temps were 40-50 degrees the whole time but the cabin temp was 80 deg F. when I returned! HVAC was "off" and no preconditioning schedule was active. The last thermostat setting was 70 deg.

Right now the car is in a public garage charging with 110V. Temp in the garage is 71 but, again, the cabin temp is 80 deg.

What is happening? Thanks.

If the car was in the sun, I'd be surprised if it wasn't 80F. Inside a garage, no real idea, but charging itself does add some warmth somewhere.