Bosch Washer Error Code Er:04

Er:04 on a Bosch washer indicates a door control fault. The error points to a problem with the Triac semiconductor component, the control module, or oversudsing that is disrupting the door lock circuit. The washer stops operation when this code appears to prevent running with an improperly controlled door lock.

No. The Er:04 code signals that the washer cannot reliably control or verify the door lock, and the machine is designed to halt operation when this fault is present. Running a washer with a compromised door lock circuit creates a risk of the door opening during a cycle, which could cause water damage or injury.

A reset may temporarily clear the code, but it will return if the underlying fault has not been corrected. If oversudsing caused the error, clearing the suds and allowing the machine to reset may resolve it for good. If the Triac or control module is faulty, the error will reappear as soon as the machine attempts to operate the door lock circuit again.

If oversudsing is the cause, you can resolve it yourself by running a rinse cycle, reducing detergent use going forward, and switching to an HE-rated detergent. If the fault persists after ruling out oversudsing, the Triac or control module will need inspection and possible replacement, which typically requires disassembly of the machine and comfort working with electronic components.

If oversudsing is the cause, there is no parts cost involved. Triac repair or control module replacement typically involves parts costs ranging from roughly $50 to $300 or more depending on the specific board, plus labor if a technician performs the work. Getting a diagnostic visit from a qualified repair technician will give you a more accurate estimate for your specific model.