Seized Callipers? - How to Diagnose?

[msportpanda]

I've left my Z4M sitting for a few months and noticed the front left brakes are quite hot and squeaking at low speeds.

I assume this is a seized calliper, can this happen from letting a car sit for an extended period of time?

Before I go ahead and replace both front callipers, are there any quick or easy wins that I can try as a DIY solution?

Also noted that since I've owned the car, the brake pedal can be pushed to the floor with the engine on, could this point to a slow failure elsewhere, perhaps a master cylinder issue?

Would like to try and diagnose it properly so I don't end up just chucking parts at the car so any guidance would be much appreciated.

[msportpanda]

Thank you for the guidance everyone, really appreciate it. Will get the car up on stands tomorrow and check the pad carriers and slide pins before I go for a new calliper.