E3 error during warm-up; machine attempts to heat but times out, coffee is lukewarm or cold.

Safety first: Unplug the coffee maker and wait until all internal parts are cool. Heating components operate at mains voltage.

Diagnostic steps:

• Visual inspection: Remove the housing to access the thermoblock. Look for burnt connectors, darkened insulation, or a tripped/burned thermal fuse attached to the heater body.
• Check thermal fuse: Many Gorenje thermoblocks have an inline thermal fuse. With a multimeter (continuity mode), test across the fuse. No continuity means it is blown and must be replaced with the same temperature and current rating.
• Measure heater resistance: Disconnect heater terminals and measure resistance. A typical small thermoblock may read 20–60 Ω. Infinite resistance indicates an open heater coil.
• Inspect PCB side: Trace heater wires to the control board. Check the heater relay or triac for burn marks or cracked solder joints. Reflow suspect solder joints if you are experienced with electronics.
• Reassembly: Replace any damaged components with Gorenje-compatible parts. Ensure all spade connectors are tight and insulated.

Warning: If you are not trained to work on mains-voltage heating circuits, do not attempt live testing. Seek a professional technician.