E50 motor brushes worn out or faulty motor.usually its motor brushes with less than 10mm of carbon left that causes this fault.remove the brushes from the motor and check.you can stretch the carbon bit by pulling it and refit to motor to temporary check the motor/machine then works OK.DO NOT USE IT LIKE THAT AS IT CAN DESTROY THE MOTOR COMMS!!!.replace brushes with new ones if all seems well after stretching.Laying machine on its back gives access to motor brushes
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December 2011