LiftMaster 41D3452 Limit Switch Kit

The LiftMaster 41D3452 Limit Switch Kit is a direct replacement assembly for select LiftMaster and Chamberlain residential chain-drive garage door openers that use mechanical travel limits. This kit restores accurate open and close stopping points by providing the contact switches that the opener’s rotating limit mechanism actuates during travel. It is commonly used to correct symptoms such as the door overrunning the header, stopping short, or failing to consistently recognize learned limits—issues that arise when worn or faulty limit contacts no longer signal the control board correctly. Designed for Security+ era AC-motor openers that employ mechanical limit cams, the 41D3452 serves as a compatible OEM-style repair part; buyers should confirm compatibility by checking their opener’s parts list or the identification label inside the head unit for the exact part number.

Installation typically involves disconnecting power, removing the opener’s light lens and cover to access the drive head, swapping the existing limit switch assembly with the 41D3452, securing the harness, and then re-adjusting the open and close travel limits per the opener’s owner’s manual. After replacement, test the full open/close cycle and verify the safety reversal system with a 2x4 obstruction test as recommended by the manufacturer. This replacement limit switch kit supports reliable travel feedback for residential applications and helps extend the service life of compatible LiftMaster/Chamberlain chain-drive garage door openers when limits no longer hold or cannot be set reliably.