Well, folks, here's a strange part. I have the crank cam assembly in
my hand now, and I'm looking at what appears to be the electrical
contact
part, and nothing seems to be broken. What I'm looking at is a main
crank
consisting of a flat piece with the knob at one end (for the wiper arm
that's
under the hood, which extends to the other wiper), sandwiched between a
cam on one side (with a notch that a spring loaded pin pops into when
the
cam rotates and locks), and another sort of cam on the other side with
a
slot in it. This last flat cam has the electrical contact piece on it,
and is
attached to that center, main flat crank piece against a tiny,
slinky-sort of
spring like a string wrapped around the separating disk.

All that complication being said, it SEEMS to me like this assembly is
meant
to allow the crank to move around separately when the wipers are stuck
somehow,
so the motor doesn't labor too much and burn out. Extra stress on one
of the
wiper arms (the rods under the hood, that is, not the blades above)
causes that
pin to be pulled out of the slot, and the cam on the top to turn free.
I assume
the spring is meant to exert friction to prevent the pin and cam from
rotating
in normal, non-stuck operation.

Bottom line -- it LOOKS like whatever has happened, the cam is back in
a
"normal" position (pin's back in the slot, cam's rotated back to where
it was),
and there's no damage. I just don't see how these three pieces of flat
metal
are in anything other than normal relative positions. If they're not,
of course,
I'd be able to rotate whatever it is back to normal.

I've got a FEELING that this clever mechanism is intended to absorb
that abuse
and allow a mechanic (or the driver) to simply force the mechanism back
into
a "normal" orientation.

This has me MUCHO INTRIGUED. And if it's not so, I just don't see the
reason
for all this monkey-motion hardware. If it IS so, wow. VERRRY clever.
And,
considering how much stress wipers can be under in various weather
conditions,
quite reasonable (especially considering that wipers are a major, often
ignored,
critical safety feature).

All we need is a GM engineer to spill the beans :-)

Mark