Kenmore Range Error Code E0 21

E0 21 indicates a communication break between the User Interface Board and the Pan Sense Board. These two boards share data so the range can detect cookware and control cooktop output. When that communication link fails, the range displays this code to signal a wiring or board-level fault.

Start by checking the wiring harness that runs between the UIB and the Pan Sense Board, as loose or corroded connectors are the most common cause. Reseat all connectors firmly and inspect the harness for visible damage. If the connections are secure and the error persists, one of the two boards likely needs to be tested and possibly replaced.

If the issue is simply a loose or corroded connector, repair costs may be minimal, covering only a service call fee in the range of $75 to $150. If a wiring harness needs replacement, parts and labor could bring the total to $150 to $300. Replacing a failed UIB or Pan Sense Board typically costs between $200 and $450 depending on parts availability and local labor rates.

A hard reset by cutting power at the breaker for several minutes can clear the code if the fault was caused by a transient voltage spike or a temporary software glitch. However, if the underlying cause is a loose connector, damaged harness, or failed board, the code will return once power is restored and the system attempts communication again.

Operating the range while this error is active is not recommended. The Pan Sense Board provides data the control system uses to regulate the cooktop, and using the appliance without that communication functioning correctly could result in unpredictable behavior. It is best to resolve the fault before resuming normal use.