Hi.
Switch around the plugs at the water valves and press the water lever at the fountain.
If the icemaker fills up - replace it.
If not - check the continuity of the solenoids and replace the bad one.
Check if the inlet tube is frozen. If it is - replace the water
valve
Part number: 61005626 
Here are the breakdown diagrams and
Replacement parts for Maytag MZD2766GEB REF - SXS/I&W | AppliancePartsPros.com
Thank you.
Simon.