How do I raise the feed dogs in a Brother LS2125 sewing machine as they seem to be lowered?

https://www.youtube.com/watch?v=SsEp0XfUEf8
How do I raise or lower the feed dogs?

1. Raise the presser foot lever, and then slide the drop feed lever.
2. Set the lever in the. position for normal sewing.
3. The feed dogs can not be raised only by sliding the drop feed lever to . Raise the feed dogs as described below. Slide the drop feed lever to .https://support.brother.com/g/b/faqend.aspx?c=gb&lang=en&prod=hf_pq1500seuk&faqid=faqh00000058_000

If you are referring to fabric not feeding through...make sure the feed dogs were not accidentally lowered. There should be a switch/lever to raise and lower feed dogs. May have to remove extension tray/table to have access to switch. NOTE: even if switch is moved, the hand wheel will have to be rotated at least 1/4 a turn before results from switch selection becomes "active".

Joyce, Some machines do not have adjustable feed dogs. Do a Google search your make and model# manual or how to lower feed dogs. Check the attached links,instruction and guides, Good luck
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How do raise or lower the feed dogs Brother
Tutorial Adjusting Feed Dog Height and Position ABC Sewing Machine
What Are Sewing Machine Feed Dogs and How Do they Work

On page 35 of your manual (see link below), there are instructions for darning. It looks like your machine needs to have the darning plate installed over the feed dogs before you can perform darning or free motion quilting. If you do not have the darning plate, then you will need to get one.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CFAQFjAH&url=http%3A%2F%2Fecx.images-amazon.com%2Fimages%2FI%2FB1dzfyluFLS.pdf&ei=jkMpVYmGFsWzoQTryICoCA&usg=AFQjCNEBTgKmXv2EyHiiw-px33CFogPHXA&bvm=bv.90491159,d.cGU

Yes, there definitely could be something wrong, but there are some things you should check. Most machines are capable of raising and lowering the feed dogs; yours might be fully or partially lowered, so that while it moves, it's not far enough up to the surface to move the fabric. Using the lever or dial, LOWER it all the way, then RAISE it all the way, but you're not finished. It will still not raise until you turn the hand wheel TOWARDS you (ALWAYS towards you on every machine) at least one and possibly two revolutions. You'll then SEE and most likely HEAR it click up. I know someone who got a steal on a Brother marked defective because the feed dogs wouldn't raise, so she brought it home, turned the hand wheel two revolutions, and viola! The feed dogs raised!

Sounds almost as if the feed dogs are canted or angled instead of being level. That's an adjustment you would need to get into the lower mechanics for. Other than that I can only wish you luck.

sounds like something may have broke or come loose,, I'd take the machine to someone else to have it checked to see what the poping sound was

Do you have the darning plate over your feed dogs? Read your manual, to see what the problem is. If, you do not have a manual go to www.brother-usa.com under support and download your manual for free, when you enter your model number-LS2125

Not sure what you mean.

If you are referring to the feed dogs - they do not drop or disengage.
Instead, there is a cover that is used - part # XA3442-121

If you do not have a manual, you can download (free) at the Brother website.

I was having trouble with this too, but found more help online...you have to switch the dog feed back to 'up'....then turn the needle wheel toward you....the feed dog should snap back into place :)
Hope this helps :D