GDO Craftsman buzzing sound door won't open or close

newday3000December 22, 2008

I have Craftsman 1/2HP 139.18850 (1995).

The door or remotes won't open the door and I found another post that seems the same problem. "When pressing the wall button or outside keypad the motor (41A4315-7C) hums twice and does nothing. The green light up on the motor blinks 5 times, stops, blinks 5 times and so on"

Seems to indicate...The LED is blinking the code for "RPM sensor or motor overload".

I bought the 41C4398A RPM sensor assembly part and replaced it and the same problem happens so it's not the sensor itself.

My gears (worm, drive) look fine to me, a little chewed but still look 100% fine to me.

What else could cause the RPM sensor to stop the motor from turning? Is there some way to force turn the mechanism to see if it's jammed on a gear or tooth.

Not sure what to try next.


Thank you for reporting this comment. Undo

The RPM sensor will not stop the motor from running. There is a possibility the start capacitor is bad if your door is closed and will not open. If the door is open and will not close it could be the trolley is jammed against the bolt just in front of the motor housing. What was your original symptom?

    Bookmark   December 22, 2008 at 3:39PM
Thank you for reporting this comment. Undo

Thanks for the info. I used a couple of posts here to figure it out and fix it. I fixed it just now using this information.

Is the trolley (the thing the door is connected to) jammed against the bolt just in front of the motor unit? If so you can remove that bolt and then run the opener until the door is closed. While it is closed adjust the 'up limit' a couple turns in the opposite direction of the arrow printed on the cover? That control is on the side of the unit. Be sure to replace the bolt.


    Bookmark   December 22, 2008 at 3:43PM
Sign Up to comment
More Discussions
Wayne Dalton i-Drive vs. Belt Drive vs. Screw Drive
Hello All, I am looking to install 2 new garage door...
who makes a 10x8 "Carriage House" style garage door?
Perusing the websites of most of the major garage door...
Turning part of garage into storage/man cave/laundry
Some background in my project: 1. I need a study, so...
garage door remote opens but wont shut door
I have a 10 year old Craftsman garage door opener model...
What's the Lowdown on Garage Door Brands??
I have read some prior posts on steel garage door brands...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™