The parking brake caliper pads rust out and fall apart. It happened to me. I replaced it myself tho for much much cheaper.
Hardest part of the job is to knock out the pins if they are corroded.
Its electric so no bleeding required.
Put the car in tow mode and jack mode.
Unbolt wheel.
Unclip harness from parking brake
Unbolt parking brake caliper .
Take out pins
Replace with new pads
Unbolt the servo motor on back of caliper
Manually rotate gears to draw back piston
Reinstall motor
Rebolt caliper
Plug harness back in
Rebolt wheel
Hardest part of the job is to knock out the pins if they are corroded.
Its electric so no bleeding required.
Put the car in tow mode and jack mode.
Unbolt wheel.
Unclip harness from parking brake
Unbolt parking brake caliper .
Take out pins
Replace with new pads
Unbolt the servo motor on back of caliper
Manually rotate gears to draw back piston
Reinstall motor
Rebolt caliper
Plug harness back in
Rebolt wheel