Transmission fault light is on

Welcome to 2CarPros.

If the light is on, you need to have the computer scanned to identify diagnostic trouble codes related to the transmission. Often times a parts store will scan it for free or lend or rent a scanner to you. Here is a quick video showing how it is done:

https://youtu.be/YV3TRZwer8k

Having the computer scanned is where I recommend starting. Otherwise, it will become a guessing game.

Let me know what you find so I can better direct you,

Take care,
Joe