Model #CST4 Official Horizon treadmill
Here are the diagrams and repair parts for Horizon CST4 treadmill, as well as links to manuals and error code tables, if available.
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Showing 10 of 136 parts
Safety key
Grip pulse
Symptoms for treadmills
Repair guides for treadmills

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the motor correctly.

A worn walking belt will begin to slow down during use. If your treadmill walking belt is worn out, replace it using these steps.

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn't run.
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