Blink 4-3

How to Fix It

1. Power-cycle the opener.

   Switch the breaker for the garage off, wait 60 seconds, switch it back on.
   Some 4-3 events are transient memory glitches that clear on a fresh boot.
   If 4-3 doesn't return after a normal cycle of opening and closing, the board recovered.
   Monitor for recurrence.

2. Check for moisture damage.

   If your garage is humid or has had any flooding, water on the logic board causes intermittent 4-3 events.
   Open the back of the opener and look for any white powder, green corrosion, or water staining on the board.
   If found, the board needs replacement.

3. Order a replacement logic board.

   Match your opener's model number to the correct logic board part number.
   Chamberlain sells direct, plus most local parts retailers.
   Don't get a generic universal board — they may not have all the features your model uses (smart features, learn buttons, etc).

4. Install the new board.

   Power off the breaker.
   Disconnect all wiring from the old board, noting where each wire goes (take a photo).
   Remove the old board (typically 4 screws).
   Mount the new board, reconnect wires per your photo.
   Power on and run the learn procedure to pair remotes again.

5. Re-pair remotes and re-set limits.

   After board replacement, all remotes and the keypad need to be re-learned.
   Press the learn button briefly, then press a button on the remote.
   Repeat for each remote.
   Re-set travel limits per the manual.