I just changed out my rear heater core this weekend.   After the the
re-installation I now only have the high (3rd) fan speed.
The low and medium settings no longer function.  All three speeds worked
before!
My leak is fixed now but I have a new aggravation.  I took the shroud
back off and disconnected and reconnected the wiring thinking there
might have been a bad connection but nothing changed.
While I had everything apart I blew it all down with an air hose but
everything was solid and nothing seemed to be wagging or flapping.
I can't believe the problem could spontaneously occur at the switch on
the dash and there is only one fuse that controls the blower (right?) so
the problem must be at the motor itself.
Anyone got any insight on how to approach this?   I could live with just
one rear blower speed (high) but I don't want to!

Thanks,
          John McLean   87  Vanagon  GL