!!
critical Keurig

Error Code 3

The Brewer must be descaled now.

? What Causes This

When 4 dispense cycles in a row take longer than expected to brew, indicating mineral buildup.

How to Fix It

Have your Keurig Authorized Distributor descale the brewer immediately to prevent damage.

Source: page 16 of the official manual

From the manual

Manual page 16 — Keurig error 3

This error code appears in:

Keurig Coffee Maker