How do I know if my LiftMaster 030DCT circuit board is bad?

Common signs include no response from the opener despite confirmed outlet power, intermittent or erratic operation, remotes or wall control not activating the door, or visible damage on the board such as burn marks or corrosion. Before replacement, rule out simpler issues like a tripped breaker or GFCI, a locked wall control, damaged wiring, or sensor problems.