Display shows E4 and the coffee maker beeps and refuses to start brewing.

Safety first: Unplug the coffee maker before inspecting the drip area.

Check carafe position:

• Ensure the glass carafe is fully seated on the warming plate and pushed all the way back so it engages the drip-stop lever under the filter basket.
• Remove and reinsert the carafe a few times to free any sticking parts.

Clean the drip-stop mechanism:

• Open the filter basket area and locate the spring-loaded drip-stop plunger at the bottom of the brew basket.
• Clean around the plunger with warm soapy water and a small brush to remove dried coffee residue.
• Operate the plunger by hand (with the unit unplugged) to ensure it moves freely.

Internal switch check (advanced):

• Remove the bottom cover to access the carafe / drip-stop microswitch (usually located near the front, aligned with the carafe position).
• Verify the switch actuator moves when the carafe is inserted.
• Test the switch with a multimeter for continuity when pressed. Replace if it does not change state.

If cleaning and reseating the carafe do not clear E4, the drip-stop switch or its wiring is likely faulty and should be replaced.