Samsung Dishwasher Error Code AC2

AC2 indicates a communication failure between the Main PBA and the Inverter PBA. The Main PBA has not received a response from the Inverter PBA for 2 seconds, causing the dishwasher to pause the cycle. The system automatically shuts off Inverter Relay 1 for one minute and then retries the connection repeatedly until communication is restored.

The AC2 error causes the dishwasher to pause and prevents the wash cycle from completing normally, so continued use is not possible until the fault is resolved. Running diagnostics while the unit is paused is safe, but you should not attempt to bypass the error and force operation, as the Inverter PBA controls the wash motor and an unresolved communication fault could indicate an underlying electrical issue.

If the fix involves only reseating a loose connector, there is no parts cost and minimal labor if done yourself. A replacement wiring harness typically falls in the range of $20 to $60 in parts. An Inverter PBA replacement generally runs $80 to $200 or more depending on the model, and a Main PBA can cost $100 to $300 or higher, with professional labor adding to those figures.

A knowledgeable DIYer can start by checking the CN1 connector on both the Main PBA and the Inverter PBA for loose connections, damaged pins, or corrosion, as this is the first recommended diagnostic step. Reseating a loose connector requires no special tools and may resolve the fault immediately. If the wiring harness is damaged or either board needs replacement, a repair technician with experience on dishwasher electronics is advisable.

A power reset may temporarily clear the displayed code, but if the underlying cause, such as a loose connector or a failed board, has not been corrected, the AC2 error will return once the dishwasher attempts to run and the communication failure reoccurs. Address the root cause of the fault before relying on a reset as a solution.