Rubber smell?

Check the serpentine belt, one of the pulleys may be seizing causing the belt to drag on it. It's may not be something that you can just see, may have to loosen the belt and then spin each pulley by hand. Running hot/overheating can also smell like burning rubber. Actual burning rubber is very acrid. Pop the hood and let engine get up to temp, check if thermostat is opening and coolant flowing.

If the belt is okay look for wiring that is contacting the exhaust.

a/c vents have a strong chemical / electrical smell a/c and fan work fine

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