What AC4 / AE4 Means
AC4 and AE4 refine the general AC/AE communication error on WF45-series front-loaders (WF45M5500A, WF45H6300AW and related models): Samsung’s service documentation for these models ties this specific number to the Wi-Fi module losing contact with the main board, rather than the display or another board. It sits inside the same communication-error family as AC/AE, naming which module lost the connection.
Common Causes of AC4 / AE4
- Wi-Fi module connector to the main board loose or unseated
- Wi-Fi module itself failed
- Momentary loss of communication after a power dip
🔧 One Safe Check You Can Try
Treat it the same as any AC/AE code: with the washer powered off for two to three minutes, restore power and restart the cycle. Since this is the Wi-Fi module specifically, wash functions should keep working even if AC4 or AE4 returns; only the SmartThings connection is in doubt. If a wash cycle itself is interrupted, or the code keeps returning, Samsung’s instruction is to request service.
⚠ Why You Shouldn't Go Further Than That
- The Wi-Fi module and its connector are behind the control panel; confirming the problem sits with that module and not the main board is a technician’s measurement, not a guess from the code alone.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.

