Oven light, fan, and display work but food takes much longer to cook than before

Safety first: Disconnect power before testing elements.

• Mode comparison: Test different modes (conventional, grill, fan‑assisted). Note which modes heat poorly to identify the suspect element.
• Element resistance tests: Measure resistance of each heating element (lower, upper/grill, convection ring). Replace any element that is open or significantly out of specification.
• Check recent wiring changes: If the oven was recently serviced or installed, verify that all element wires are correctly connected according to the Etna wiring diagram.