- Power-reset the appliance once and check whether the code clears.
- Think back to any recent installation, rewiring, outage, or electrical work before the fault started.
- Do not keep restarting the appliance if the same electrical code returns immediately.
Mains voltage is too high. On the Gorenje HID965GC, this code relates to the range cooker and should be interpreted together with how the appliance is behaving right now.
- The range cooker displays U400 instead of normal status information.
- The current cycle, function, or startup sequence may stop, pause, or behave differently than expected.
- The same code may return after a reset if the underlying issue is still present.
- The appliance detected abnormal supply voltage, incorrect wiring, phase issues, or a power event.
- A control circuit or power component is not receiving the electrical conditions it expects.
- If the appliance was newly installed, have the wiring and supply checked against the installation guidance.
- If the code followed a power outage, record whether other electrical symptoms are present too.
- Persistent wiring or voltage faults usually need an electrician or authorized service visit.
- Do not open live electrical panels or wiring unless you are qualified.
Book service or an electrician if U400 returns after one reset, especially if the appliance was recently installed or the issue followed supply work or a power event.
Can U400 clear after a reset?
Sometimes a temporary glitch clears after one full reset, but a repeated return usually means the same underlying issue is still there.
Should I keep using the appliance if it works again briefly?
Only if the code stays away and the appliance behaves normally. If the same code comes back, stop and move to service or more targeted diagnosis.