Maytag Washer Error Code E304

E304 indicates an overvoltage alarm (OV2) from the Mitsubishi inverter drive that controls the washer's drum motor. The inverter detected that its internal DC bus voltage exceeded a safe limit and shut down to protect its components. This fault is most commonly triggered by a severe load imbalance during the spin extraction phase, though power line surges and hardware failures can also cause it.

The washer is designed to stop operation when E304 triggers, which is a protective response. Running a cycle with a corrected, balanced load after clearing the error is generally safe for a one-time occurrence. However, if the fault recurs, continued use risks further damage to the inverter drive and motor, and the washer should not be operated until the underlying cause is diagnosed and resolved.

If the fix is simply redistributing the laundry, there is no parts cost. If the Mitsubishi inverter drive requires replacement, parts and labor typically range from $200 to $500 or more depending on your region and the specific model. DC bus capacitor replacement, if performed as a component-level repair, may fall at the lower end of that range. A service diagnostic call alone generally costs between $75 and $150.

If the fault was caused by an unbalanced load, you can redistribute the laundry evenly in the drum, clear the error, and restart the cycle. If the error returns repeatedly without an obvious load imbalance, the cause is likely a hardware issue such as degraded inverter capacitors or a failing inverter drive, which requires a technician with experience working on inverter-controlled motors. Do not repeatedly run the washer if the fault recurs, as continued inverter stress can cause additional component damage.

A power reset may clear the E304 code temporarily, allowing the washer to resume operation. However, if the root cause, such as a load imbalance, line voltage surge, or component failure, is not corrected, the fault will return. A reset is a useful first step to determine whether the event was a one-time occurrence, but it is not a repair.