Looks like there are a few possible solutions...
From the list:
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the problem is under the plastic wiper motor cover. There is a tab of metal
that is not grabbing a plastic wheel. If you run the wipers with the cover
off you will see this metal tab will skip over the plastic wheel. Fiddle
with the metal tab and the wipers will park. It is in the pulse washer
system actually, not the wipers. when you go to reinstall the wiper motor
cover make sure you have the plastic wheel under the cover in the right spot
or it will not bolt on correctly. Hope this helps.
Kevin Livezey
Doylestown PA
SY #2054
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For those that emailed me and asked me to send them what I found out.. this
seems to be the consensus... thanx Ron
> folks on the S-10 list claim the
> "mystery wipe" (tm) is a problem
> with the turn signal switch itself.
>
> Some have tried messing with
> the ground of the board that is
> on the wiper motor, but that
> doesn't always work.
>
> Everyone that has replaced their
> switch [yep...in the column] has
> fixed the problem
>
> My '87 Blazer did it
> My '91 Blazer did it
> My Sy started it.
> Several other S-trucks I know of
> have that disease
>
>
> Ron
>
>
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Moose here;
Haa, the mysterious wiper wipe.
It's not the turn signal lever, it's the switch way down deep inside.
I've cleaned this switch twice, but it's starting to cycle again.
You've got to remove the steering wheel and the guts behind it along
with the wiring down the steering column. It's a pain, but doable without
special tools, well except one.
I don't know the part number but it's a black square shaped housing
with, um, about six wires.
You might want to replace the lever anyway if the markings are
rubbing off.
See Ya
Glendale, CA
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