Question about Sears Craftsman LiftMaster Chamberlain Garage Door Opener Wireless Keypad Model 976LM Security+

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1993 Liftmaster professional mod. 1345. Have adjusted door balance, spring tension, new safety sensors (correctly aligned). With trolley disengaged from door the trolley will run approx. 8 - 10 inch. & stops. Have adjusted chain tension, no luck. I suspect a problem with either gears or logic board. Any ideas?

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Most likely is a bad IR sensor board. This is a small printed circuit board just in front of the motor.

Posted on May 03, 2010

Testimonial: "Thanks. Given the age I think I'll just get a new chamberlain."

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Posted on Jan 02, 2017

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