Liftmaster 41C4398A RPM Sensor Assembly

WAS OPEN PACKAGE BUT WORKED ON LIFTMASTER MODEL 1260 (1993)THE PLASTIC BLACK RING WAS DIFFERENT DIAMETER SIZE BUT WORKS WITH REDESIGNED CIRCUIT BOARD.I OHMED OUT NON WORKING AND THIS NEW ONE AND ALL WERE THE SAME VALUE, EVEN DIODE CHECK, I PUT OLD BACK IN AND STILL FAILED. THIS ONE WORKED.I MUST BE MISSING SOMETHING. DID NOT TRY TO POWER TEST IT OUT OF CIRCUIT.IF DID NOT WORK I WOULD HAVE RETURNED AS PLASTIC BAG WAS OPEN AND I BOUGHT NEW UNIT NOT SOMEONE ELSES RETURN AND POSSIBLY DAMAGED ONE.ANYWAY IT IS WORKING.

I was having issues my garage door only opening up 6-8 inches. I wasn’t sure what it was. I thought I had to pay a garage door company for a new opener and installation. I then went on YouTube and was able to troubleshot the issue. Many said it was the RPM Sensor. I purchased this on Amazon and it arrived the next day. Installation was easy and now my garage door is back to normal.

Hi, I have an old Sears 1/3 HP opener, model 139.53000 I believe, circa 1995. (It's so ancient, the numbers have faded.) The correct rpm sensor part can't be found anywhere.I mistakenly bought this part and was initially disappointed that it had an additional black plastic mounting piece that wasn't going to fit. Although very similar, the board on the new piece was a bit smaller than my old board, just enough so that drilling new holes wasn't an option.My old board had two discrete components on the board --an infrared LED and a matching opposing receiver/transistor. The new board comes with these two components packaged in a unified housing. It so happens that the pinouts of both are exactly the same, which meant soldering the new part to the old board would work, and it did, saving me from buying a whole new opener.If you know how to solder (and desolder) and are going to take this route, make note of the diode (arrow) symbol on the unified part (which is somewhat hard to see). The diode side goes closest to the 4-pin plug. There are also two little plastic stand-off nubs on the bottom of the unified part that should be cut flush so that the part hugs the circuit board.Also, I had to keep and reuse my original black plastic rotary interrupter part, as it has a smaller diameter.

Easy to install. Works like a charm. After trying all sort of fixes and failing I found a guy on the net who recommended changing this part for my problem. The door was opening partially erratically.

Clear instructions, easy to install however my Chamberlain opener still does not work