If at power-up, the machine beeps but the needle does not move, then turn on the power and wait 8 seconds. After 8 seconds, if the machine begins to beep continuously, there is a problem with the motor drive. On APQS machines, take the top two screws out of the black back panel and open it. Look at the motor belt to make sure it is secure and intact. Inspect both pulleys to make sure thy are secured tightly and are able to move. If they are loose, tighten the set screws. Make sure that one set screw comes in contact with the flat part of the shaft.
If the machine beeps once, it may be a shorted single stitch switch that puts the machine into setup mode. Make sure that both of the handle switches are released. On Gammill machines, if the red switch is shorted, the channel lock will also not work. When you have determined which switch is shorted, you can purchase replacement switches from Radio Shack or www.quilttech.com. For instructions on replacement, go to :