Oven fan runs but there is no or very low heat in hot air (convection) mode; F05 may appear after some time.

Safety first: Turn off the circuit breaker and verify the oven is de-energized before removing the rear panel.

Step-by-step checks:

• Access the ring element: Remove the rear cover of the oven. Locate the circular heating element around the convection fan housing.
• Check element continuity: Disconnect the element terminals and measure resistance with a multimeter. Typical values are 20–40 Ω. An open circuit (OL) means the element is faulty.
• Inspect terminals: Look for heat damage, discoloration, or loose spade connectors. Clean light oxidation and tighten or replace damaged connectors.
• Check wiring to power module: Trace the wires from the element to the power PCB. Repair any burnt or broken wires using high-temperature-rated cable.
• Replace the ring element: If defective, remove mounting screws inside the oven cavity (around the fan cover), pull the element out carefully, and install the new V-ZUG ring element, ensuring correct positioning and secure connections.

When to call a technician: If the element tests good but F05 persists, the heater relay or power module may be defective and should be tested and replaced by a qualified technician.