my wiperblade on a c280 not working,you can hear the power when you turn on the

What do you hear with switch on, the motor run?

This wiper set up on your vehicle is different than most. It has a wiper motor, linkage and a pivot assm. Usually if you can hear and see a slight movement it is that the motor is working but restricted by a seized pivot assm. Sometimes you can remove, clean corrosion (aluminum oxidation) and lubricate and get working. other times it is too deteriorated and needs to be replaced. Also be warned that the wiper motor has been "stressed" by this restriction in movement and can become damaged. If it is still working after freed up it may have a reduced life due to the stress and die out soon after. This can all be evaluated by a qualified technician. If you have any further questions feel free to stop by and have it professionally inspected. Sincerely, Your Curt's Service Team 248-545-0500