E27 Moderate Easy DIY

Bosch Dishwasher E27 — Low supply voltage

Bosch Dishwasher · Error code E27

What E27 Means

The control board has detected supply voltage below the operating threshold. Cycle is halted to protect electronics.

Symptoms

  • Random shutdowns
  • E27 in the evening when other appliances run
  • Cycle never finishes

Common Causes

1
Brownout / undervoltage at outlet

House voltage sagging during heavy load periods.

2
Shared circuit overload

Dishwasher sharing a circuit with disposer or microwave.

3
Loose outlet or junction box connection

High-resistance neutral causing voltage drop under load.

4
Extension cord or undersized wiring

Long undersized run feeding the unit.

How to Fix It

  1. Measure outlet voltage at the dishwasher (should be 108-132 V).
  2. Measure under load (with heater on) to see if it sags below 108 V.
  3. Confirm the dishwasher is on a dedicated 15 A or 20 A circuit per spec.
  4. Tighten outlet, junction box, and breaker terminals (with power off).
  5. If voltage still sags, have an electrician evaluate the supply.

More Bosch Dishwasher Codes

E01 E01 — Control board fault E02 E02 — Heating element / NTC sensor fault E03 E03 — Water not heating E04 E04 — Water flow / flow meter fault E05 E05 — Overfill / float switch tripped E06 E06 — Door switch / lock fault

All Bosch codes → All dishwasher codes →

Verified against manufacturer documentation: bosch-home.com

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.