Machine shows E11; milk frothing function is disabled or stops mid-cycle.

Safety: Unplug the machine and ensure it has cooled before disassembling the milk system.

• Clean milk circuit: Disassemble the milk frother, nozzle, and suction tube according to the manual. Soak parts in warm water with a food-safe cleaner to remove milk residues.
• Run cleaning program: Use the automatic milk system cleaning program if available, with the recommended AEG milk system cleaner.
• Inspect seals: Check O-rings and seals on the milk connector for cracks or deformation and replace if worn.
• Check temperature sensor: On models with a dedicated milk temperature sensor, verify its connection and test resistance. Replace if faulty.