The doors are locked, It seems the vacuum pump does not work. Theredbuttondoesno on 1991 Mercedes-Benz 500SL

The red button does not help, the key does not open the doors Is there a schematic we can use to hook another engine to get a vacuum sorce and which port to use. Is there a schemantic as to the placment of the hoses.Where can we buy a repair manual. Does Mercedes have a web site that will help us. I will never buy a Mercedes after working on this one,

Asked by for the 1991 Mercedes-Benz 500SL
seek diag and est this needs to be looked at for proper diag