Rear wiper motor 93ZJ

[DougW]

That was fun.

Yea.. usually I take pictures but this was messy
and I was lazy. :P

This is what it looks like.
http://omix-ada.com/rear-wiper-motor-93-94-jeep-grand-cherokee-zj.html

$359 Holy shit! Well, it is built well and lasted
20 years with only one problem so far. Can't bitch.
..yes I can.. :) Why replace something when you
can fix it for far less $$$


The ZJ's rear wiper was sticking in the up position
so I figured it was the contacts inside that detect
when the wiper reaches the end. 99% of the time
this is the case.

Once you get the unit out you have to separate
the top case (simple plastic tabs)

Then the circuit board has to come out. The
only way to do that is to unsolder the motor.
Fairly big tabs but a little heat and lifting
will separate the wires.

There is a little catch right in the center
of the circuit board. Don't pry the board
from the edges, pinch the catch and lift the
board or you can crack it.

Turning the board over you see two relays some
diodes, and the contact block.

The contacts on the board were encased in a black
crispy goo that used to be the dielectric grease.
Time and heat dried it into a crispy mass that was
wedging under the contacts. Solvent, brush, easy
enough. A bit of new dielectric grease and we're
done.

Now to get to the main gear.

Four bolts later the inner plastic case was off
and that exposed the gear with it's copper traces.
Just like the shifter position sensor, the traces
were a bit corroded and covered with more black
crud.

Wire brush, bit of air, and a new layer of
dielectric grease.

Reassemble the unit, solder the motor back on
and button it all up.

YAY! it works!

Spent more time trying to find a thinwall socket.
That inner plastic is held on by bolts and there
just isn't any space to get a regular socket on
one of them.

--
DougW