Kurt Thomas wrote:

> van wont start. Fuel pump relay switching constantly (buzzing).  Remove fuel
> pump relay buzzing stops (of course) plug back in, it comes back.  Swapped
> relays no change.

        If the fuel pump relay is switching that fast and swapping the
other relay in that little black box causes the same behavior (that
second relay does not have the timer unit built into it of course),
then I believe you have a problem with either the relay ground or
something before the fuel pump relay - such as your iginition switch.
A standard relay like the digifant power relay (the other relay in
that little black box) will only switch on when current is passing
through the switching circuit (and if the relay is still any good,
it will turn off when the current stops flowing it). If measure the
voltage across the fuel pump relay's switching circuit and it is
fluctuanting, then you know it's not the relays. If the voltage from the
iginition switch (ground your multimeter to a know good
ground) is fluctuanting, then the problem is before the relay.
I forget where those relays ground - might be at the post just
below the box - you might want to clean that ground point up while
you are at it...

dave
from the iginition switch  If the digifant
relay is actually making the noise, it could also be dying...