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C-Series Treadmills Service Checklist Diagnosis Guide

  • Updated

Applies to the Following Treadmill Models: CT800 (All Models), CT850 (All Models)

Problem Solution/Cause
Display does not light
  1. Safety Key/Tether Cord is not in position.
  2. Circuit breaker on front grill is tripped. Push circuit breaker in until it locks.
  3. Power cord/plug is disconnected. Make sure cord/plug is firmly pushed into proper wall outlet.
  4. Breaker panel circuit breaker may be tripped.
  5. Treadmill defect. Contact the Spirit Service Department.
  • Tread belt does not stay centered
  • Treadmill belt hesitates when walked/run on
 The user may be walking while favoring or putting more weight on either the left or right foot. If this walking pattern is natural, track the belt slightly off center to the side opposite from the belt movement. See our article: "How to Adjust Treadmill Belt Tension and Set Tracking."
Motor is not responsive after pressing START
  1. If the display moves initially but stops after a short time and the display shows the error code 'LS,' see our article on troubleshooting the LS error.
  2. If you press START and the belt never starts moving and the display shows 'LS,' see our article on troubleshooting the LS error.
Treadmill will only achieve approximately 7mph speed but shows higher speed on display This indicates the motor should be receiving power to operate but there is low AC power to the treadmill. Do not use an extension cord. If an extension cord is required, it should be as short as possible and a minimum of 16 gauge weight. See our article: "Treadmill Power Supply Requirements."
Treadmill trips on board 15amp circuit

This indicates high belt/deck friction. See our articles:

If after cleaning/lubricating your treadmill the problem persists, check the amp draw of the motor. If this is high and there are signs of significant wear on the deck, it may need to be flipped if it is on its original side.
Computer shuts off when console is touched while walking/running on a cold day Treadmill may not be grounded/grounded properly. Static electricity is likely crashing the computer. See our article: "Treadmill Power Supply Requirements."
Circuit breaker trips, but not the treadmill circuit breaker

Check that the treadmill is the only appliance in the circuit. See our articles on power supply and equipment safety:

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