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The CYBOT problem pages - Motor Checking

Quite a few people raise questions regarding motor operation.

Before taking cybot apart or getting violent with it, check the batteries!


ABOVE: CORRECT motor placement.

ABOVE: CORRECT plug position and wiring.

Please observe the following:
  • Motor placement, with respect to wire colour.
  • Plug placement, with respect to wire colour.
  • Plug wiring, both plugs, location of black and white wires.
  • Motor wiring, white wires should connect to the outer motor connections.

If any are incorrect, you may get reversed motor operation.

Your options are:
  • Contact Eaglemoss about this, they will replace it.
  • Email me, I will change the wires over for you (UK only).
  • Change the connections yourself if you have the ability.
  • Ask your local TV/electical repair shop, they may do it for a small fee.


  • Do you have grease in the gearbox? (check it anyway)
  • Ensure you do not have too much grease in the gearbox
  • It is possible to overtighten the gearbox, try loosening the screws slightly
  • Some people have removed any burrs from the gear wheels, improving operation
  • Some people have suggested placing washers on the gear shafts to space the gears


Remove the motor PCB screws and withdraw the pcb. Plug the motor test board in.
Ensure that the connections on the PCBs do not come into contact with metal or other pcb's
  • If only one motor does not operate, swap the plugs on the motor pcb
If the same motor fails to operate, the motor is likely to be at fault.
To be sure, remove the motor from the gearbox and try again.
If the motor begins to spin, strip and rebuild the gearbox.
If the fault moves to the other motor, the motor pcb may be faulty.

When you turn the wheels, or push cybot along, the motors act as small dynamo's.
As such they generate electricity, injecting current into the motor board - this can damage cybot.
The advice here involves slowly turning the wheels for a few moments.

  • GENTLY turn each wheel, you should feel slight resistance
  • If a wheel is stiff to turn, unplug it from the motor board and try again
If you get a noticable difference, you may have a fault with the motor board.
Swap the connections as above and try again.
If the other motor bcomes stiff to turn, the motor PCB may be faulty

If a motor fails to operate where the other motor did, the motor has a fault.
Carefully check the connections and wires for signs of broken off wires.