Error 7, Can't Slow Down on Cybex Steppers 400s and 500s, Tectrix Climbmax 1000

Probable Cause

An error 7 seen on the Cybex/Tectrix stepper models 400s, 500s and Climbmax 1000 indicates a speed problem. Possible causes for the error 7 are the following:
a) Faulty RPM sensor
b) Faulty RPM disk

Corrective Action

a) Check the RPM sensor; Replace if necessary.
b) Check the RPM disk; Replace if necessary.