Samsung Dryer Error Code AC4

AC4 indicates a communication error between the WIFI PBA and the MAIN PBA on a Samsung dryer. The two boards are unable to exchange data signals properly. This fault is detected during line test mode and is most commonly caused by faulty soldering on the WIFI module or a defective WIFI board.

The AC4 error relates to the WIFI communication board and does not directly affect the core drying functions of the appliance. However, this error appears in a line test diagnostic mode, so the dryer may not be in a normal operating state. It is best to resolve the fault before returning the unit to regular use.

If the fix involves only reflowing or repairing solder joints on the WIFI module, labor costs could be modest, typically in the range of $50 to $150 depending on your service provider. If the WIFI PBA needs replacement, parts and labor combined can range from $100 to $250. A MAIN PBA replacement, if required, would be a more significant repair, potentially ranging from $200 to $400 or more.

Start by removing the WIFI module and carefully inspecting all solder joints for cracks, cold joints, or bridges. If soldering looks acceptable, check that the wiring harness connecting the WIFI PBA to the MAIN PBA is fully seated and undamaged. If the connection and soldering are good, replacing the WIFI PBA is the next step. A defective MAIN PBA is a less common but possible cause if the WIFI module swap does not resolve the issue.

A simple power reset is unlikely to permanently clear the AC4 error because it is caused by a hardware communication fault, not a temporary software glitch. The underlying issue, such as faulty soldering or a defective WIFI module, must be corrected for the error to clear in line test mode. Resetting may temporarily clear the code display, but the fault will return when diagnostics are run again.