Pull out the power cord before opening up anything. Double check that correct powercord is disconnected! This procedure is not possible without getting close or even touching the power mains connectors inside.

If you can't get access to the back panel without disconnecting the water hose, ensure that water is disconncted before taking off the water hose. It's bad to not having coffee, but having your kitchen area hosed down in water does not help.

Remove the two T15 torx as shown in the picture. A flat head 4 bit can also be used.

Pull the back panel out from the bottom. Some force might be needed. Set panel aside.