Garage door closes, then open back a bit by itself!

[mangomanhere]

Hello Experts.

My background: I am not electric/electronic qualified.

My garage door closes and opens on press of a button. There is a black box (connected by a chain) - I believe this is the central controlling unit. I have attached pictures of this.

Recently, it opens back on itself after reaching the floor! It doesn't open back fully, just about 30cm from the floor.

What could be the issue?

Thanks in advance.

 

[Andy™]

either something in its way or the limits need adjusting

 

[mangomanhere]

either something in its way or the limits need adjusting

Nothing obvious that I can see. Ocassionally, it does stay shut.
How do you adjust "the limits"?

 

[Andy™]

side of the motor. 2x screw adjusters. usually takes an allen key or screwdriver

 

[mangomanhere]

I had a look. Nothing like that could be seen. Attached are the pics.

 

[Andy™]

thought it was a shutter... its probably that yellow block on the belt needs moved

 

[UNG]

Looking at the OP the panel photo shows what looks like a teach button which may suggest that the limits are set electronically

Another thought given the door closes then it pulls back a short distance are all the tracks / control arm joints clean and well lubricated

 

[mangomanhere]

Regarding "...are all the tracks / control arm joints clean and well lubricated"
Today I will give it a rub down with a clean cloth. Then spray WD-40?

 

[Spoon]

Then spray WD-40?

Not always the best choice.
Get something like 3-in-1 Oil or Duck Oil

 

[Geoff1946]

WD = Water dispersant . Then it dries. waxy. Not an appropriate general lubricant.