Treadmill goes from very fast to slow to fas againt, very irratic, then just stops.

Have the buttons been used alot ? Sounds like to me the buttons are getting worn out

Hi There, hmmm.... am I hearing that the treadmill starts too fast? At over 1mph? Most US treads will start at 1MPH and some will allow selection of .5MPH in the maintenance mode settings maybe. Otherwise, this could be attacked by a technical crew, like jatinah electronics possibly. If the treadmill would be set at one speed only that could be accomplished by reducing the drive signal at the component-level. It is certainly workable, but I would need to know what the current speed is that is too fast for her, and her ideal speed. ;o)

Ok. So the first thing to try is to calibrate the speed.
You do this by doing the following:

• With the SAFETY KEY in place, hold the ELEVATION UP and SPEED DOWN buttons for five seconds. The console will beep twice, "ENG0" will appear in the Distance window, and a number will appear in the Elevation window.
• Press SELECT until "ENG3" appears; this is for Auto-Calibration.
• Press START to Auto-Calibrate.
• The treadmill will calibrate minimum and maximum speed, and minimum and maximum elevation. When Auto-Calibration is complete, the treadmill will reset to User's start screen. This process takes three to five minutes.

Make sure there are no errors. . .and that the speed goes from super slow to super fast and then stops. . .. if it stays slow. . or stays fast. .or error code appears during calibration, there is a problem.
If after a good calibration sequence, if it still does the stopping and E-1 after 10 seconds. ., then you need to (Power off and disconnect treadmill). . .then unplug the speed sensor from the lower power board, blow into the connector on the wire, and add a little contact cleaner spray to the connector on the board.
Recap: If it actually runs. . .but stops after a few seconds. . but the calibration runs and passes fine. .. .more than likely it is a speed sensor misread or a faulty speed sensor.

If someone spilled a drink on the belt, it will become sticky as it dries. The belt will try to stick to the bed of the treadmill. Loosen belt, wipe clean the bed, underside of belt, and end rollers.

hi.
i think the problem is with your touch switch panel.
regards,
nuwan

the motor is bad. will need motor and controller board

schwinn has a life time warranty on all there frames

This condition is when the treadmill goes to full speed as soon as you power up the treadmill. Typically when this occurs, it is an indication of a short circuit in the motor controller.

http://webpages.charter.net/chestnuts/Trimline%20Owner%27s%20Manual-1600-2600-3600-4600.pdf