2015 mustang. side door inside near latch. What are those numbers?

[inachu]

What do they do?

There is also number buttons on the driver side visor.

 

[The Boston Dangler]

What do they do?

There is also number buttons on the driver side visor.

they tell you things about your car, like its name and age and tire pressure.

by "number buttons" do you mean the sticker telling you to wear your seat belt?

 

[The J]

Are you referring to number buttons on the door near the open handle? If so, those might be for seat position memory if your car had power seats.

The number buttons on the driver side visor are for Homelink, which allows you to program the buttons to, for example, open your garage door.

Have a look at the owners manual to confirm this.

 

[LTC8K6]

What do they do?

There is also number buttons on the driver side visor.

Driver memory buttons on door?

Homelink buttons on visor?

EDIT - Confirmed:

http://www.fordservicecontent.com/F...-Owners-Manual-version-3_om_EN-US_03_2015.pdf