As far as the water system you just need to clean/replace the water filter.
Prepare the Ice Maker For Cleaning
Step1Lift the power located above the ice maker storage tray. Step2Unplug the refrigerator. Step3Allow the refrigerator and to defrost. This will melt any large blocks of ice that have accumulated in the ice maker.
Clean the Ice Machine
Step1Remove the ice machine storage tray. Step2Dump any water in the ice machine storage tray. Step3Wash the ice machine storage tray using warm, soapy water. Rinse and allow to dry completely. Step4Sanitize the lines of the ice maker. Consult your manufacturer's directions for steps to do this, because it's not available on all models.
Reassemble the Ice Maker
Step1Replace the ice machine storage tray. Step2Plug the refrigerator into the outlet to restore power. Step3Lower the internal power bar located just above the ice machine storage tray. This allows the ice machine to make new ice.