Bosch Washer Error Code E:21

E:21 means the drain pump ran longer than the allowed time without successfully draining the drum. The washer stops the cycle to prevent potential issues from standing water or pump overload. The fault points to the drain pump, the drain hose, or the wire harness connecting the pump to the control board. Bosch diagnostic test P15 is the recommended starting point for isolating the exact cause.

No, you should not continue running wash cycles while E:21 is present. If the washer cannot drain properly, water will remain in the drum, which can cause mold growth, unpleasant odors, and potential leaks. Continued operation with a failing pump can also put additional strain on the motor and connected components. Resolve the drain issue before resuming normal use.

If the fix is simply cleaning the pump filter or clearing a kinked hose, there is no parts cost and only your time is involved. If the drain pump motor needs replacement, parts typically range from 40 to 120 dollars depending on the model, with professional labor adding roughly 80 to 200 dollars on top of that. Wire harness repairs or replacements fall in a similar range. Getting a diagnostic from a certified technician before ordering parts is advisable if test P15 does not clearly identify the faulty component.

Start by cleaning the drain pump filter, which is the most common cause of this error and requires no tools or parts. Next, inspect the drain hose for kinks or blockages and confirm it is routed correctly. If the filter and hose are clear, run diagnostic test P15 to evaluate pump operation and check the wire harness for damaged connectors or broken wires. If the pump motor itself has failed, it will need to be replaced.

A reset may temporarily clear the error code from the display, but the fault will return as soon as the washer attempts another drain cycle if the underlying problem has not been fixed. Resetting without addressing the cause does not resolve the clog, hose issue, or pump failure triggering the code. The reset can be useful for confirming whether a one-time obstruction has been cleared after you have performed the physical inspection and cleaning.