Machine displays E03 and stops; water does not heat or only lukewarm coffee is dispensed.

Safety warning: Disconnect power and allow the machine to cool fully. The heater and boiler can remain hot for several minutes after use.

Diagnostic steps:

• 1. Confirm symptom: Start a brew cycle and feel (carefully) near the steam wand or coffee outlet after 1–2 minutes. If no warmth is felt and E03 appears, the heater is likely not energizing.
• 2. Access heater terminals: Remove the top/rear cover to expose the thermoblock or boiler. Identify the two main heater terminals and any inline thermal cutoffs.
• 3. Check wiring: Inspect spade connectors for discoloration, burning, or looseness. Tighten or replace damaged connectors.
• 4. Test heater resistance (advanced): With the machine unplugged, measure resistance across the heater terminals. A typical value is 20–60 Ω. Infinite resistance indicates an open heater that must be replaced.
• 5. Inspect thermal cutoff: Many Electrolux coffee makers use a one-shot thermal fuse on the heater. Test continuity across the fuse. If open, replace with the same temperature rating and investigate causes of overheating (scale buildup, blocked flow).

Note: If the heater and thermal fuse test good, the fault may be a failed heater relay or triac on the main control board, which usually requires board replacement by a professional.