AGA Elise or Mercury induction stove
showing U400
U400 tells you the induction stove was wired to the supply incorrectly.
Mon–Sat, 8am–8pm
- Control board and power
- Control board and display repair
- Source: AGA
Book a visit
Three short steps, about a minute.
or call (844) 415-7620
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What U400
actually means.
U400 tells you the induction stove was wired to the supply incorrectly. About a second after it powers up, the control shuts down and leaves the code on the display until the connection is fixed, so it tends to appear the first time the stove is switched on after installation or electrical work.
AGA stove display
What to do when U400 shows on the stoveKind of codeControl board and power
The main board failed its own start-up check, lost contact with the display, or saw the supply voltage sag too low, often after a storm, a power outage or a spill that ran down behind the panel. The breaker, the cord and the outlet are ruled out before a board is replaced. A stove that sparks, smells of hot wiring or keeps heating while this code shows is switched off at the breaker first.
Usually leads toControl board and display repair
Stoves with a blank or flashing display, touch keys that do not answer, codes that keep returning or a stove that will not turn on, traced to the board, the keypad or the power to them.
Shows up asStove Error Code
The stove shows letters and numbers, a flashing symbol or a short message, beeps, and the oven or a burner stops or will not start.
MakeAGA
A British name in home cooking, part of the Middleby group, best known for the cast-iron stove that stays warm all day.
SourceAGA Elise 36 Induction owner's guide
Elise and Mercury induction models; usually seen at first power-up after installation or electrical work.
Before you book,
in this order.
Each step comes from AGA's own guidance for U400 on its stoves. Follow it to the end: the last card says whether this is a visit.
Turn the breaker for the stove off and keep it off.
Do not keep resetting it to see whether the code clears.
Book a visit so the electrical connection can be checked and corrected.
Still there?
It usually turns into control board and display repair. Book with the code and the model number.
What not to do
U400 is not a worn-out part inside the stove. It concerns how the stove was connected to the house supply, so the fix starts at the connection, not at a board.
What you may
notice with it.
The stove problems U400 tends to arrive with. Answer these at the stove before anyone is booked.
All problems
Where U400 usually leads
Control board and display repair.
AGA
stoves.
A British name in home cooking, part of the Middleby group, best known for the cast-iron stove that stays warm all day.
AGA stove repairMore AGA codes
All 15 AGA codesControl board and power on other makes
Gas stove
A stove with gas burners on top, whether its oven below runs on gas too or on electricity, fed by one gas line behind it and plugged into a wall outlet for the spark.
Induction stove
A stove with a flat glass top that heats the pan itself through a magnetic field, run by touch keys and power boards, with an electric oven underneath.
Heritage stove
Classic stoves built the old way, from AGA cast-iron heat storage stoves to French and Italian enamel stoves with brass trim, kept for decades and repaired rather than replaced.
In AGA's own words
The range has been incorrectly connected.
Every code on this site is taken from the manufacturer's documentation, never from a forum or a parts listing. Elise and Mercury induction models; usually seen at first power-up after installation or electrical work.
AGA U400 stove repair,
where we come out.
The same visit in every metro below: the code, the model number, and a diagnosis before any part is ordered.
All service areasTampa BayFL · 31 areas
Miami / South FloridaFL · 47 areas
New York MetroNY · 75 areas
HoustonTX · 36 areas
ChicagoIL · 50 areas
Los AngelesCA · 95 areas
San DiegoCA · 31 areas
Questions
about U400.
Can I clear U400 myself?
My new AGA Elise showed U400 the first time it was turned on. Is it defective?
Why does my AGA induction top switch off a second after I turn it on?
Can U400 appear on my AGA after an electrician worked in the house?
Back to your everyday
Still showing U400?
Book with the code written exactly as the stove shows it, the full model number, and whether you notice any smell of gas or hot wiring — when there is a code, that is where the diagnosis starts.