So this brake warning light can come on because 1/2 of the brake master cylinder is not working. I would stop driving the car until the repairs are made. The other two reasons the brake warning light can come on is low brake fluid or the e brake is still on. Yes, please check the brake pads first both front and rear, check for leaks as well, use a flashlight to help.
But from what you have said the master being bad is what I think is wrong with it. You will need to bleed the brake master before installing it, this video will show you how.
https://www.youtube.com/watch?v=WDxvEQrMkBg
This guide can show you more information on the brake warning light in case you need it
https://www.2carpros.com/articles/brake-system-warning-light-on
Please upload a short video in your response of the problem, so I can see what's going on. Ken
Thursday, February 26th, 2026 AT 8:29 AM