Hello, I'm Cam. Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please be detailed.
These have a seperate parking brake shoe in the rear rotors.
so this may be worn out shoes or out of adjustment.
I would start with the adjsutment.
There is a plug in the rear, bottom of the drivers side and on top of the passengers side.
remove it and use the star wheel to adjsut it.
"There is a plug in the rear" of what?
The rear bracket for the caliper, thick metal.
start with the drivers side. Lift the wheel and turn it by hand as you adjust, stop when you start to feel drag and then back it off just a bit.
If the adjustment does not work, how hard is it to replace the pad?
Not pads, shoes, the service brakes are pads, parking brake is shoes and you would need to remove the rotors and likely the hubs as well.