My 1987 300d has a clicking noise behind the push buttons sometimes and the blower will cycle on and off rapidly.Most of the time the blower won't come on at all,and I don't have power at the fusible link(both sides)unless the blower does come on.I thought it was a supply problem so I replaced the ignition switch with an OEM,but still have the problem.When it was running at one time I pulled out the push buttons the noise is not coming from them.The noise is definitely coming for behind and not on the right side kick panel.It seems like it works normal if the car has been running a long time,about an hour even the motor sound good with the control varying the speed the way it should,Im stumped.All help is appreciated,it's getting colder outside.Merry Christmas to all