Help on Garage Opener - Chamberlain PD752KDS

[f117b2]

Hi people,

I got a weird problem with the one - Chamberlain PD752KDS. I bought in April this year.

Chamberlain® 3/4 HP Chain Drive Garage Door Opener at Menards

Normally I pushed the big button once, the door opened or closed. Since last night, it got a weird problem, if pushed the button once and released immediately, the door started rolling and immediately rolled back, the lights started blinked. If I pushed and HOLD the BUTTON, the door could rolling down as long as I pushed and hold the button. If I released, it immediately rolled back.

Any ideas what the problem is????

Appreciate for any helps.

[TJR]

Safety sensor, safety sensor check your safety sensor.
Make sure nothing blocking the sensor and they are pointing straight at each other.

[f117b2]

Safety sensor, safety sensor check your safety sensor.
Make sure nothing blocking the sensor and they are pointing straight at each other.

Thank you TJR. Yes. It is the safety sensor. They are not aligned.