The brake warning light on my dash

Hello,

It sound like brake pads are at minimum value remove front and rear pads check the thickness of the pads you can detect it if the sensor is touching the disc surface that means pads must be replaced.

check our links below how to replace rear pads and rotors,

https://www.2carpros.com/articles/how-to-replace-rear-brake-pads-and-rotors

https://youtu.be/G5M_xKIxUb4

Check the diagrams below procedure how to replace rear pads and rotors, and check how to test them.

hope these helps.

thank you.