---
title: "Bosch error code U400"
description: "Bosch error code U400: the supply voltage is outside the range the appliance will run in."
url: "https://boschmiami.support/error-codes/error-code-u400/"
date_modified: "2026-08-18"
Appliance type: "Cooktops & rangetops, Ranges"
---


# Bosch error code U400

### What this one means

The supply voltage is outside the range the appliance will run in. It is a code the manufacturer publishes for this appliance, not one we have worked out — and it is decoded here rather than left as three characters on a display.

### The other ways your machine may say it

The same condition is published under more than one label, because it has been carried across generations of this appliance:

- **U400, E9000, E9010** — the same condition, on machines of different ages

### What the code covers

A published cause names a circuit rather than a component, which is the single most useful thing to know before ordering a part. This one covers:

- The building's supply
- The circuit feeding the appliance

### Worth doing before you call

- Note whether it happens at particular times of day
- Note whether other appliances on the same circuit behave oddly at the same time

### Then what

🔴 This is a code about your building, not about your cooktop. No part inside the appliance changes it, and the people to call are the utility or an electrician. Worth establishing before a repair is booked. It is also one of the very few codes that several unrelated manufacturers publish identically, because the induction module underneath is an industry part rather than a brand’s own.

This code is published for cooktops & rangetops and ranges. The [full list of codes](https://boschmiami.support/error-codes/) has the rest of them, searchable, including the labels older and newer machines use for the same conditions.

Cooktops & rangetops

What this code means

What this one means

The supply voltage is outside the range the appliance will run in. It is a code the manufacturer publishes for this appliance, not one we have worked out — and it is decoded here rather than left as three characters on a display.

The other ways your machine may say it

The same condition is published under more than one label, because it has been carried across generations of this appliance:

U400, E9000, E9010 — the same condition, on machines of different ages

What the code covers

A published cause names a circuit rather than a component, which is the single most useful thing to know before ordering a part. This one covers:

The building's supply

The circuit feeding the appliance

Worth doing before you call

Note whether it happens at particular times of day

Note whether other appliances on the same circuit behave oddly at the same time

Then what

🔴 This is a code about your building, not about your cooktop. No part inside the appliance changes it, and the people to call are the utility or an electrician. Worth establishing before a repair is booked. It is also one of the very few codes that several unrelated manufacturers publish identically, because the induction module underneath is an industry part rather than a brand’s own.

This code is published for cooktops & rangetops and ranges. The full list of codes has the rest of them, searchable, including the labels older and newer machines use for the same conditions.

---

**[Read full article: Bosch error code U400](https://boschmiami.support/error-codes/error-code-u400/)**