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,
Check the diagrams below procedure how to replace rear pads and rotors, and check how to test them.
hope these helps.
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Monday, March 15th, 2021 AT 6:09 PM