What E:30 Means
E:30 is the mirror of the undervoltage record: the machine has measured mains voltage above 140 volts in North America and has shut itself down. Bosch again points the action at the house wiring rather than at the appliance. Voltage that high on a nominal 120-volt circuit usually indicates a neutral problem, which affects everything else plugged in nearby as well.
Common Causes of E:30
- Open or high-resistance neutral in the house supply
- Incorrect wiring or a miswired outlet at the appliance
- Supply irregularity upstream of the property
🔧 One Safe Check You Can Try
Stop using the dishwasher and look at what else in the house has been misbehaving: lights that brighten and dim together, other electronics failing early. Those are the signs that go with this code and they belong to an electrician, not an appliance visit.
⚠ Why You Shouldn't Go Further Than That
- Overvoltage from a neutral fault can push well beyond 140 volts on one side of the panel, which damages electronics throughout the house.
- This is diagnosed at the panel with the load on, not at the dishwasher, so appliance work misses it completely.
- Neutral faults are a recognised fire and shock hazard and are licensed electrical work in most jurisdictions.
- Restoring power to the machine before the supply is corrected risks destroying the power module that has so far protected itself by shutting down.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.