What should I do if my brewer displays Error Code 4?

Error Code 4 means the float switch is lower than it should be while the CWT inlet valve is open and the time limit is exceeded. Likely causes include the inlet water being disconnected, low water pressure, the inlet valve not opening, the CWT level sensor stuck low, or leaks. Check your water supply connection and pressure, and contact your Keurig Authorized Distributor if the problem persists. (Page 16)