Three display numbers for one fault: the voltage reaching the cooktop is out of range. Bosch points to the utility or support.
Model compatibility: Bosch reuses codes across series and model years, so U400 / E9000 / E9010 may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.
Plain language
What this code means
U400, E9000 and E9010 mean the supply voltage is incorrect and outside the normal operating range.
One problem hides behind three numbers on Bosch cooktops: U400, E9000 and E9010. The supply voltage is incorrect, in other words outside the range the cooktop is designed for. Bosch describes all three the same way and gives the same advice for each.
Whose number is it?
The electric cooktop section lists U400.
The induction section lists E9000 and E9010 as a pair.
The induction section also lists U400 within a combined entry that includes E9011.
Bosch gives no reason why some cooktops use U400 and others E-numbers. For Bosch it is a single fault.
Supply voltage explained
It is the electricity that reaches the cooktop from the electrical panel of your home. Too high or too low for the cooktop, and one of these codes appears.
Bosch’s instruction
No reset for owners is listed. You are told to contact the electrical utility provider, or Bosch Customer Support. The order says something: voltage belongs to the supply, and no button on the cooktop can alter it. Leave the junction box closed and do not test the circuit yourself, because a cooktop circuit carries enough current to cause injury.
The E9011 pairing
Where the induction entry joins U400 and E9011, Bosch names an additional cause, a cooktop that is not connected correctly. With E9011 on the display, read that page as well, since the wiring might need a look next to the supply.
Useful notes for the utility or a technician
The number exactly as shown.
Dimming or flickering lights when the code appears.
Other large appliances misbehaving simultaneously.
A start following an outage, a storm or electrical work.
Bosch cooktop service in Los Angeles for supply faults
After the utility has checked the supply, call (310) 879-1577. Tell us which of the three numbers appears and what the utility found. See the cooktop repair page for more.
Important safety warning. Do not attempt repairs involving electrical components, gas, water lines, refrigerant or sealed systems. Unplug the appliance if it is safe to reach the outlet, and leave internal diagnostics to a qualified technician.
Seeing this code on your Bosch appliance?
Book a specialist visit for a clear estimate and approval before any repair.
