I have a 1989 Caprice Station Wagon. All of a sudden the windshield
wipers will not shut off, once I turn them on. I have to unplug the
cable going to the wiper motor. Then it shuts off until I use the
What is causing this? How can I fix it? (hopefully without repalcing
the wiper motor). Wipers do work ok except for this.
There is a known problem with the pulse board on GM products that can cause
problem. I had it happen on an almost new Oldsmobile company car of that
In my case,the company shop did a repair on the pulse board. It had
do with the motor itself.
I think you may still be able to get the replacement boards.
I had almost forgotten this problem which should be added to my bitch list
We had a '91 Caprice 9C1 (police) that did this. We always just shut the
ignition key off for a split second and turned it back on to kill the
wipers. Since the 700R4 isn't electronic if we were going at highway speed
the wheels would keep the engine turning and we could be slow about it, in
town you had to be quick unless it was manually downshifted.
On Sat, 18 Sep 2010 14:11:57 -0500, "Daniel who wants to know"
Thanks for the info. I'll see if I can get a replacement board (I
assume it's inside the wiper motor housing).
If not, the key idea sounds good, and I was thinking to cut one wire
going to the motor and put a switch under the dash to shut it off.
But getting the right wire may be tricky.
I'm not fond of the idea myself, but it's either that, or pulling over
to unplug the motor wire. I suppose I could pull over and shut off
the key. However, I plan to install an under dash switch, unless I
can get a replacement board. They want almost $100 for a rebuilt wiper
motor. I can get a under dash switch and some wires for less than $5.
So, I think the switch wins. Now, I only have to determine which of
the 3 wires to cut to install the switch. ????
It's an old car, so I'm not going to spend a lot on a wiper motor that
still works, just wont shut off.
It is not likely the wiper motor that is your problem.. The pulse board
controls the variable speed wiper,
and these boards from GM are known to have weaknesses.
I believe you can find a new (aftermarket, thank goodness) board for less
than $30 online.
I'll google it for you if you wish.
I dont think I ever heard exactly what the problem was. They had some
semiconductor problems during this time span on window control board,
computer, etc but dont know if that was involved with this. You know,
pulsed systems can be a bit hard on components if they are not well
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.