Although most home treadmills are designed for easy operation, there are some common problems that are inevitable. The console may not display. Perhaps a loose or slipping running belt poses a safety hazard. Maybe the treadmill runs at an unpredictable speed. Those are just some of the things that can happen to bring your workout to a halt. While certain repairs will require the services of a professional who specializes in treadmill maintenance and repair, there are some basic repairs that you can do yourself.
Clean and routinely maintain the running belt. The belt may be worn if the treadmill stops operating or trips the circuit breaker. Look for any tears in the belt. Test the belt by putting the treadmill at full incline. If it does not shut off, you may need to replace the belt. You can try lubricating it first, but the safest fix is simply to replace it.
Tighten the running belt if it is loose. A belt can slip if there is too much friction. Be careful not to tighten the belt too much, though. You should be able to lift the belt at least 3 inches.
Push the belt in the direction that it normally turns. Turn off the power before you start. If the belt is difficult to turn, there is high belt/deck friction. However, if the belt moves freely, that's not the problem.
Examine the roller sleeve to see if it is centered on the running belt. If not, this could cause the belt to move to one side. Often a common problem with treadmills, you can try making adjustments yourself, but eventually you may need to replace the sleeve or roller.
Stop the treadmill and immediately unplug the power cord from the outlet if you notice a burning smell. Overheating could be a sign that there is too much friction or a short in the wiring. Examine the belt and deck for any signs of wearing. If they check out alright, inspect the wiring. Replace any damaged parts as needed.
Check to make sure that the power switch is on if you suddenly lose power. If this isn't the cause of the power loss, unplug the treadmill from the wall outlet and individually test the fuses, breakers and switches. Test the wall outlet first, as a fuse may have blown or a circuit breaker tripped.
Allow the treadmill to run at a speed of 2.5 mph without anyone walking on it if you notice fluctuations in the speed. The speed should be constant. If not, there could be a problem with the motor.
Test the motor using a fully charged lantern battery. The motor should still operate at slow speed.
Replace the batteries in the panel if it dims. If the batteries aren't the problem, check to see that all the wiring is still intact. Sometimes a wire pulls loose.