Kenmore Dryer Error Code F-42

F-42 means the motor control board has detected a line voltage below 90 VAC, which is too low for the dryer to operate safely. Electric dryers require a full 240 VAC supply, and this code triggers when that voltage drops below the acceptable minimum. The fault is most often caused by a tripped circuit breaker, a loose terminal block connection, or a damaged power cord. Running the DIAGNOSTIC: Displaying Line Voltage routine and TEST #1 are the recommended first steps.

No, you should not attempt to run the dryer while F-42 is active. Operating a dryer motor under sustained undervoltage conditions can overheat motor windings and damage the motor control board. The dryer's control system triggers this fault specifically to prevent that damage. Leave the dryer off until the power supply issue has been identified and corrected.

Repair cost depends heavily on the root cause. Tightening a loose terminal block connection costs nothing beyond the time to diagnose it. Replacing a power cord typically runs in the range of $20 to $60 for the part, plus labor if a technician is involved. A circuit breaker replacement at the panel may cost $50 to $200 depending on the breaker type and whether an electrician is needed. If the motor control board itself has failed, board replacement parts generally range from $80 to $250, with additional labor costs if professionally repaired.

Some causes of F-42, such as a tripped breaker or a loose terminal block connection, can be addressed by a knowledgeable DIYer who is comfortable working with electrical components. However, work at the terminal block involves exposure to line voltage and should only be performed with the dryer fully unplugged. Diagnosing whether the problem is in the breaker, the cord, the terminal block, or the motor control board requires a multimeter and a systematic approach following the TEST #1 and line voltage diagnostic procedures.

A power cycle may temporarily clear the fault display, but F-42 will return as soon as the motor control detects the undervoltage condition again during operation. Because the root cause is an electrical supply problem rather than a software glitch, resetting alone does not fix anything. The underlying supply issue must be corrected before the code will stay cleared.