# LiftMaster code 3-5: the door won’t close, or it reverses partway

Source page: https://garagedoorscience.com/code/liftmaster-error-codes/3-5

## The door won’t close, or it reverses partway

On this wall-mounted opener, a cable tension monitor watches the door’s cables. It may be reporting a problem or be disconnected, or the opener may still expect a second monitor that was removed.

**Check this first, then a pro.** Clear anything in the door’s path. If a second monitor was taken off, unplugging and plugging in the opener three times makes it forget that one. Anything to do with the cables themselves is a job for a pro.

Don’t lift or force the door by hand: if a spring is broken, the door can fall. Springs and cables are a pro’s job: DASMA, "Do not try to remove, repair or adjust springs or any door parts or mounting surfaces, such as wood blocks, steel brackets, cables or other like items. Because of potential dangers involved, all repairs and adjustments must be performed by a trained door systems technician using proper tools and instructions." (https://www.dasma.com/wp-content/uploads/2023/04/TDS167.pdf)

From the maker’s manual:
- LiftMaster manual for models 8500WMC, 8500WMC-267, PDF page 32: https://cgi.widen.net/content/jwcqmmesfs/original/114-5706-000.pdf

Garage Door Science isn’t affiliated with the opener makers LiftMaster, Chamberlain or Genie. Each meaning is our summary of the maker’s own manual, which we link.