Feed dog on Janome 9000 will not come up

Make sure the stitch length is set higher than 2. Also make sure the feed dogs have not been inadvertently dropped for darning. If the feed dogs are up and moving back and forth, they are working okay but may have a lot of lint and dust inhibiting them from biting the fabric.

Are you sewing very fine or slick fabric? Frequently, that will cause the fabric to slip under the presser foot. Check your machine to see if you can adjust the pressure on the presser foot. If not, then try laying a piece of wax paper or vellum with the fabric. It can be easily removed after stitching.

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when the feed dogs are in the down postion the machine stay in one place
when the feed dogs are in the up positon then the machine will sew
if the machine still doesn't sew when the feed dogs are in the up position the feed dogs need to be checked to see if they need a adjustment or need to be replaced

Usually setting the stitch length to 0 (zero) lowers the feed dogs. This was traditionally used for darning.

there is a small lever at the back ( behind the bobbin case etc) that manually drops the feed dogs, also you can do it using the ADJ key. It should do it automatically when the embroidery mode or edit mode is pressed

http://www.tradebit.com/filedetail.php/32156673-janome-memory-craft-9000-instruction-manual

the sensor must not be working. I thought the 9000 lowered feed dogs automatically when embroidery option is choosen anyway. There is a manual as well as on screen drop feed dogs method for this machine

I hate to sound dismissive but: read the manual. Duh. It is not as written above: drop dog........
The feed dog is the toothed pieces in the sewing machine deck, under the needle, which move the material away from you when you push the operating pedal.
Dropping the dog - ie making it inoperative - (see manual for how to on your machine) means the material has to be propelled by hand under the needle. This is especially good for freehand machine embroidery as it means you can move the material in any direction whilst sewing.
It can be easier to freehand embroider if your material is fixed in to an embroidery hoop to hold it flat while you work.

Remove the needleplate and clean out the lint from between the teeth of the feeddogs........it is the most likely reason, the lint holds the feeddogs below where they need to engage fabric.

Check your Presser foot tension is at 3 then do a test.

If this is not sufficient the method of adjusting feeddogs is possible at home, tho perhaps not for those lacking some confidence in mechanical adjustment.......so post back for detail if needed.

The feed dog will rise as soon as you turn the handwheel one time. Just put the fabric in it and sew. It will come up automatically as long as you have moved the lever to the correct position.
sewman7

Try the emboadery slide in the back of the machine, This happened to me you just need to slide it over to the other side. It dose tell you this in your book.