My Pfaff 4874 sews 12 stitches and stops. I then press on the foot control again and it repeats. Any idea?

Try to solate the problem to machine or foot control by detaching foot control and use stop/start. If stop after a start exhibits same as foot pedal then likely the problem is machine control board else, foot pedal. Could be foot control is sticking and not completely opening or slow to open.

It sounds like the sensor connection where you plug in the buttonhole foot is bad.

Um, it could be no power to your machine, I would suspect it is the power cord, plug or possibly an internal electrical issue. If the foot control failed, the machine's light should still work.

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Press the decorative (sequencing) button again to cancel and the sequence will complete.

Did you drop the feed dogs?

yes, it is possible that the foot pedal can go out,, it would be a good
idea to have the foot pedal checked at a repair shop to see for
sure

Go to singerco.com and under customer support, look at frequently asked questions, they have alot info there. If, that doesn't work for you, call customer service at 1-800-4singer and they can advise you

PFAFF Manuals

Could be a couple of things:

1. Foot control is bad - take foot control to your local Pfaff dealer to try on one of their machines. If their machine won't run either, it's the foot control and you can look into repair/replacement.
2. Machine has a short or some type or computer board problem - take machine to local Pfaff dealer and try with one of their known working foot controls. If the machine still doesn't work, your dealer will need to diagnose what is wrong.

Hope this helps.

Happy stitching,
Kim & Linnette
www.sewingexpressions.com

Put on the C foot. Select the buttonhole stitch. The machine will start sewing in the bottom left corner of the the buttonhole. Sew the length that you need, press and release the reverse button and sew the right side of the buttonhole. When you get back to the bottom, press and release the reverse button again and the buttonhole will be finished and the thread will tie off and the machine will stop. If the buttonhole is what you want, press and release the Stop button and the machine will repeat this buttonhole as many times as you need until the machine is turned off or the Stop is pressed again. When repeating, you need not press the reverse. Just press down on the foot control and continue until the machine stops by itself.
If you don't like the first one, just sew another one using the reverse button to set the ends.