2019 Mazda3 AWD AT
Thermostat was replaced under warranty on Monday and it’s an electronic one (see my previous post).Sure sound like a thermostat issue....Find the specs for your thermostat and test it. Up until recently the specs are such that the thermostat should be at least partially open starting at 177°F and fully open by 203°F. Operating temperature should be consistent at about 185°F driving normally, up to about 205°F give or take a few depending on driving conditions, ie driving up long grades, ambient temps etc.
Test the coolant with a thermometer if you can and compare it with the gauge, see if its close.
Is your OBD scanner capable of logging cooling fan on/off cycles?
My scanner doesn't seem to have the option to log the cooling fan.
I've done multiple tests with and without climate control and it didn't made any difference.Did you have the interior heating on during this test, or was the climate control entirely shut off?