Error code
Bosch Dishwasher Error Code E27
Bosch Dishwasher E27 usually means the dishwasher has detected low mains voltage. Treat it as a power-supply warning and avoid repeated restarts.
Quick answer
E27: what does it mean and how to fix
What does it mean?
the dishwasher has detected low mains voltage.
How to fix first
Switch the dishwasher off and unplug it, or isolate it at the wall or breaker.
Why is this happening?
Low or unstable mains voltage
When should I call an engineer?
Call an electrician if the supply may be unstable, or an appliance engineer if the household supply checks out but E27 keeps returning.
What does this error code mean?
Bosch dishwasher error code E27 usually indicates insufficient voltage in the electrical supply rather than a simple cleaning or loading issue. Bosch guidance treats this as an external supply problem that may need an electrician.
Do not use extension leads, multi-plug adapters, or repeated resets to work around the warning. If the supply appears unstable, stop using the dishwasher until it has been checked.
E27 is a power-supply warning involving household voltage, the appliance power path, and the control electronics.
Symptoms users may notice
- The dishwasher may refuse to start.
- The code may appear after a power dip or circuit issue.
- Other appliances or lights may show signs of unstable power.
Why is this happening?
- Low or unstable mains voltage
- Dishwasher sharing a weak or overloaded circuit
- Power interruption or supply fault
- Internal control fault if the supply is confirmed healthy
What this usually points to
E27 is a power-supply warning involving household voltage, the appliance power path, and the control electronics.
How to fix this safely
- Switch the dishwasher off and unplug it, or isolate it at the wall or breaker.
- Do not run the dishwasher through an extension lead or overloaded adapter.
- Try one restart only after the supply is stable and the appliance is connected normally.
- Contact an electrician or appliance engineer if E27 returns.
Can I fix this myself?
MaybeYou can remove extension leads and try one normal power reset. Repeated E27 warnings should be checked professionally.
Safety boundary: Do not test live wiring, open the appliance, or keep running the dishwasher on an unstable electrical supply.
What not to do
- Do not use extension leads or adapters to bypass the issue.
- Do not keep resetting the appliance if E27 returns.
- Do not open the appliance or test live electrical parts.
Reset steps
- Isolate power for a few minutes.
- Reconnect only to a suitable normal supply.
- Stop if E27 returns or other appliances show power problems.
Intermittent vs persistent faults
A one-off E27 after a power disturbance may clear, but repeated E27 should be treated as a supply or control fault needing qualified diagnosis.
When to call an engineer
Call an electrician if the supply may be unstable, or an appliance engineer if the household supply checks out but E27 keeps returning.
Safety warning
Do not inspect live electrical parts. Disconnect the dishwasher from power and get qualified help if voltage or circuit safety is in doubt.
Useful hub links
Related power and control fault codes
Bosch Dishwasher Error Code E01
the dishwasher has detected an electronic control fault.
Bosch Dishwasher Error Code E09
the dishwasher is not heating water properly.
Bosch Dishwasher Error Code E19
a dishwasher valve or heat-exchanger related component may not be operating correctly.
Bosch Dishwasher Error Code E29
the dishwasher has detected an internal power, control, or supply-related fault.
Relevant guide
Frequently asked questions
What does Bosch dishwasher E27 mean?+
Bosch Dishwasher Error Code E27 usually means the dishwasher has detected low mains voltage or an unstable electrical supply.
Is Bosch E27 a dishwasher fault?+
It can be caused by the electrical supply rather than the dishwasher itself, so do not assume replacing parts is the first step.
Can I keep using a Bosch dishwasher with E27?+
No. Avoid repeated use until the supply is stable and the warning has cleared after one safe reset.
Model variation note
Bosch dishwasher code wording can vary by model. Use the exact model manual where available.