Ford Galaxy front windscreen wiper operation

your motor is worn out due to the arms being siezed(you'll be surprised how stiff they are and the motor still moves them) remove wipier arms then lift bonnet and remove the full mechenisum including motor. remove motor then try to move arms. if they are solid you will either have to replace this or you can disassemble them clean and grease and reassemble.(this can be fiddly) in either case a new motor will be required. make sure you get the part number off the old motor as an exact match is important. they are expensive £200+ but i got mine from E-Bay and it worked a treat.