3E has two documented meanings from Samsung: motor or power supply, depending on the platform. 3C appears in the motor family; it does not make all 3E codes equivalent.
Samsung requires consulting the manual to decide which 3E branch applies. The fact that the drum stops turning is not enough: an abnormal power supply can also stop it.
Select the path using the reference
Find the full model and the exact wording of the alert. If the manual defines it as power supply, check external conditions and report outages or tripped protections. If it defines it as motor, note whether there was movement and at what stage it was interrupted.
In both cases, limit recovery to what that manual authorizes. Do not open the appliance to test the motor, tachometer, or board, and do not use the code as a list of parts to replace.
If you do not have the applicable table, ask support to confirm it. A description from a Samsung of another generation or a table from another brand does not resolve the ambiguity, even if both show three similar characters.
Pair 3E or 3C with the model and the failure stage; keeping that distinction avoids starting a check on the wrong system.