battery charging error

Hi,

I have a 2015 Toyota tundra. When I started my car yesterday, the red battery light was ON. after couple of minutes, the voltage of the battery was fluctuating from 14 V to around 17 V and the tire pressure light was flashing when reaching 17 V. When the voltage was fluctuating, the battery light turned off and came back On when the voltage was stabilise to 14V. Sometime even the airbag light was flashing when the battery was at 17 V. Finally the fluctuation stop but the battery light is steady On. No unusual noise from the car and it's running good for now but I really want to find the problem. Any ideas of where iI should start looking to find it?

Thank!
(sorry if my english is bad sometime, I'm french)

 

Check battery connections... Clean them and tighten them up see if that fixes the issue.

 

Alternator going bad