Bosch Dishwasher Error Code E:27

E:27 means the dishwasher's control board detected a sustained low supply voltage condition, specifically below 85 VAC on US models or below 170 VAC on European models. Because the voltage stayed too low continuously, the dishwasher ended the wash cycle early to prevent damage to its components. The problem is almost always found in the home's electrical supply or wiring rather than inside the dishwasher itself.

Continued use is not recommended when E:27 is active. Sustained low voltage can cause the wash motor and heating element to operate outside their designed parameters, which can shorten component life or cause overheating. The underlying electrical issue, whether it is a loose connection or a failing breaker, also represents a potential fire or shock hazard that should be addressed promptly.

The repair cost depends on what is causing the low voltage. If the fix involves tightening loose wiring connections, a service call fee of roughly $75 to $150 may be all that is required. Replacing a faulty circuit breaker typically adds $100 to $250 in parts and labor. If the home requires new wiring or a dedicated circuit, electrical work can range from $200 to $600 or more depending on the complexity of the job.

Start by checking all wiring connections at the junction box, circuit breaker panel, and the point where power enters the dishwasher. Use a true RMS voltmeter to measure supply voltage both at idle and while the machine is running to confirm the voltage is dropping below the minimum threshold. If connections are loose, corroded, or the breaker appears faulty, those issues need to be corrected. Calling a licensed electrician is recommended if you are not comfortable working with household wiring.

Resetting the control board may temporarily clear the error display, but the code will return as soon as the dishwasher runs another cycle if the low voltage condition still exists. A reset does not address the root cause, which is in the home's electrical supply or wiring. The error will continue to cut cycles short until the voltage issue is properly resolved.