My name is***** will try my best to help you with your question.
Sorry to hear you are having this problem with your SL728 bike.
There may be a problem with the motor that controls the resistance - you can test the resistance motor using a 9 volt battery - attach a wire to positive and negative side of the battery and then touch the yellow and blue wires of the motor.
Let the motor run until it stops (if it does not stop in either direction, the potentiometer is bad and the tension motor needs replaced).
Then switch the wires around and let it run the other direction. If it works both ways the motor is good.
Next, test the wiring harness for continuity from the console to the motor. You can use a multimeter to check for continuity. If the wires check ok, you will need to check the voltage being supplied by the console through the blue and yellow wires when the tension buttons are pressed - it should be approx 6Vdc. If there is no voltage the console is defective and will need replaced.
Let me know how you get on...
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