I have a 2020 Nissan Frontier, and whenever I put the heat on in the mornings it would gradually cool down over time even though I haven’t moved the dial nor turned on “auto” on my controls. Is this a normal things for modern cars or am I looking at a potential issue with my heating system?
it’s just the blend door doing its job
You mean not doing it's job. The heat could be causing something to distort, which blocks off the heat.
I don't have a Frontier, but my heat doesn't do that.
Check the heater hoses for flow. It could also be the temperature blend door.
@imperator Just did a little research and found out it does have a temperature blend door, also I forgot to mention that it does heat back up a little bit after it cools down, so it’s very likely it’s just the blend door doing its job. Thanks for the advice!