Trouble and Countermeasure for 300D Micro Motor

Marathon Micro Motor is always the hot one on our site. And today, we would like to share some user manual of 300D Micro Motor to customers. Once you have these problems, please look through at the sheet and find the coresponding answers to repair it. 



Check Point
Power Lamp is not lighten when turning on the power switch
Is the power cord olug connected well?
Isn’t the fuse broken?
Trouble of power switch
Please inset the plug of power cord in outlet correctly.
Please replace it to designated fuse.
If it goes on continuously, then ask repair.
Please ask repair.
The motors does not work
Is the cord of motor connected well?
Isn’t the chuck opened?
Internal Circuit’s problem in control unit
Have you used a handpiece for a long time under high-load?
Please confirm whether the motor shaft rotate by hand
Please insert the motor cord in outlet correctly
Please lock the collect chuck by turning the handle to left-handed screw.
Please ask repair
Turn off the control unit, please keep it at cool place for 10 minutes and work it.
If the motor shaft does not work when the collect chuck is locked, it is problem of handpiece. Please ask repair.
Foot pedal does not work
Is the cord of foot pedal connection well?
Isn’t the Hand mode set up instead of Foot mode?
Please inset the plug of foot pedal in outlet correctly on the rear.
Please change to Foot mode by putting Hand/Foot mode button.
Foot mode is a state that the LED is turned off.
The handpiece makes noise
Isn’t foreign substance in a collect chuck?
Don’t you use it at abnormal speed?
Isn’t the bur curved?
Does the motor make noise continuously?
Please remove it after disassembling the collect chuck.(Please refer to this instruction for use)
Please adjust the RPM properly after referring to the permitted RPM for bur.
Please replace it with normal one.
Please ask repair.


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