Erratic Speed Troubleshooting - Horizon Fitness RST 5.6 Service Manual

Symptom
Erratic speeds - Upon pressing
start, belt speed increases rapidly
and then comes to a complete
stop quickly.
Erratic speeds - Upon pressing
start, belt speed increases rapidly
and does not stop.
Erratic speeds - Running belt
speed is not stable.
R S T5. 6 & R CT 7 . 6 S e a r s S e r v i c e M a n u a l 2 0 0 7
E r r ati c S p e e d Tr o ub l e s h oo t i n g
Possible Cause
Failed optic sensor.
Failed motor control board (MCB).
Machine not calibrated properly.
-Running belt is too loose or too
tight.
-Drive belt is too loose or too
tight.
Inadequate power.
Failed or improper wiring.
Inadequate lubrication on deck
and running belt.
Failed motor control board (MCB).
Test Procedure
Reference No Motor Movement
Voltage Checkpoints. (p. 21)
-Run auto calibration.
Reference Engineering Mode.
(p. 15 & p. 16)
-The running belt should not slip
at all when customer is using the
machine
-The drive belt should have
approximately 3/8 of inch
deflection.
-Check for dedicated circuit (20
amp is ideal) and check wall out-
let voltage (120 VAC). Reference
Power Source Wiring Diagram.
(p. 20)
-Make sure machine is not on
extension cord or surge protector.
-Verify there are no pinches or
cuts in the power cord, power
wires motor wires, or console
cable.
-Verify the connections of above
wires and cords.
Reference Cut Console Cable
Voltage Chart. (p. 23 & 24)
-Place hand underneath running
belt and feel for adequate silicone
application.
Reference No Motor Movement
Voltage Check Points. (p. 21)
rst 5.6 & rct 7.6 service manual 2007_rev1.0 |
Repair
Replace optic sensor.
Replace MCB.
If unit fails to auto calibrate,
refer to auto calibration
troubleshooting.
-Tighten running belt. Reference
Owners Manual. (p. 14)
-Tighten drive belt
If the AC voltage is missing or
incorrect, check the AC service or
consult an electrician.
Replace parts as needed.
Apply silicone.
Reference Lubrication
Procedure. (p. 27)
Replace MCB.