LiftMaster garage door opener: Code 4-3: 4 UP flashes, 3 DOWN flashes
Motor speed lost while closing: the motor slowed unexpectedly, and the door stops and reverses just before it touches the floor.
Applies to: LiftMaster and Chamberlain Security+ 2.0 and Security+ 3.0 openers with UP and DOWN arrows; codes 3-5 and 5-5 only on the wall-mounted jackshaft models 8500W/RJO70, 98022/RJO101 and 98032. What you see: the UP and DOWN arrows, 4 UP flashes, then 3 DOWN flashes.
Covers Chamberlain openers too: the two brands share one published table, so each code has one page here.
What LiftMaster says to do
- LiftMaster says to inspect the door’s path and tracks, remove anything in the way, check the rollers and hinges for obstructions or wear, then try the door again.
LiftMaster’s safety line: “Never adjust or loosen the door’s springs, cables, pulleys, or brackets yourself, they’re under extreme tension.” Where a spring, cable or balance problem shows up, its page says to stop and contact a local garage door professional.
No repair advice of our own. The steps above are only LiftMaster’s, as its page states them; semiatic gives no repair instructions of its own. For anything beyond them, LiftMaster’s page and a trained door technician are the authority.
Source
LiftMaster’s own help page, read on the date shown.
- Chamberlain Group Support (LiftMaster and Chamberlain): Garage Door Opener | Diagnostic Codes and UP/DOWN Flashing Lights — LiftMaster and Chamberlain Security+ 2.0 and Security+ 3.0 openers with UP and DOWN arrows; codes 3-5 and 5-5 only on the wall-mounted jackshaft models 8500W/RJO70, 98022/RJO101 and 98032. support.chamberlaingroup.com Checked 2026-09-29.
Other LiftMaster codes
Find a code by which light flashes and how many times, on any maker’s opener →