300 sd losing locking vacuum
 

my 1984 is losing central locking vacuum. now only the driver's door will open.
is it a fuse problem or is it a vacuum pump problem?
thanking in advance for any help or advice. - francis

You may have a vacuum leak so you need to get a vacuum tester and try all you lines, start under the bonnet . Or even the pump is leaking check all the little rubber joints,and elbows, and connections for cracking .

thank you mr forced induction. - francis

Jusat to add that if the one door is opening then the fuse will be ok, and the fuse will be in the fusebox under the hood .Pump location behind the trim on righthand side the trunk