C5 Newb

Hey everyone,

I have a problem that has been on here many times concerning the wipers running all the time.
The problem usually seems to be the circuit board on the wiper motor.
Most of the threads keep stating it's because the drains are plugged which gets the motor wet. Mine are NOT plugged and are very clean and unobstructed.
I bought a new motor & circuit board and installed it and everything worked great for 2 days then it started again.

Any other ideas as to what could be causing it?
I would REALLY like to get this problem fixed.

fmvette9

When my wipers started acting similar, I checked the connector going to the wiper control board and discovered the wipers were being commanded on. Traced it to the push button on the stalk.

C5 Newb

Thanks, I guess I will replace the stalk next and hope that odes the trick.

fmvette9

Check the connector first with a multimeter. You can purchase a multimeter for a few dollars at Harbor Freight, and it only takes a few minutes of testing to VERIFY the fault. Also if it is the stalk, it has a high probability of being the washer button since the other wiper speeds require mechanically moving the stalk. If your multimeter test confirms the stalk is the fault, the button can be removed. Be careful, there is a small spring. That will trigger both the wipers and washer to operate when the ignition is on. Once the button is removed, you can see two sets of contacts in the stalk. Slip small slips of paper between them to deactivate the wiper / washer. If the slips of paper fixes the wipers being on, you know the button is the fault. I drove with that solution until I found a used stalk I removed the button, and installed it into my original stalk. Much simpler than replacing the stalk.

C5 Newb

Thanks for the info, do you have more detailed info on how to test at the plug? (I have a good multi-meter)

fmvette9

You need the wiring diagram and pin out of the connector from the service manual. The stalk works by grounding the pin for the wiper speed selected. If the washer button is faulty, the low speed wiper pin will be grounded without the button being pushed in. Get a service manual, it will pay for itself many times over.

C5 Newb

I pulled the washer button and yeah, the spring shot out but I found it.
Putting paper between the contacts stopped the problem so That was an easy diagnose. Thank you!
Now I will just buy a new stalk I guess......well, a used one anyways.

fmvette9

One other tip. You can remove the slip of paper in the washer contacts (rear contact) and reinstall the button. Gives you back the washer function, and you can move the stalk down to activate the wipers. Takes off the pressure to find a new button!

C5 Newb

Okay, with the paper in between the contacts it seemed to stop the problem.....then it started again.

I replaced the stalk and it still does it......?

The motor & circuit board have been replaced.....
The Stalk has been replaced......

What the crap else could it be?!?!?

I am lost. Could it be a wire grounding out somewhere between the stalk and the motor?

fmvette9

Do a search for the post, "wipers won't turn off BC, Lucky"
It contains a schematic and connector pin diagram. Looking at the diagram, the stalk is supplying various voltages to the C, D, E pins of the motor control board, and not pulling them to ground as I previously stated. Start with the ignition off, and use the ohm settings to measure the resistance to ground of the motor controller connector pins. Make sure Pin A has a very low resistance (under 1 ohm) to ground, and pins C, D, and E have a very high resistance (open circuit) to ground. With the ignition on, use the voltage setting to measure the voltages on the pins. B should have battery voltage, and the other pins should be at zero volts.
And yes, it could be a short to ground or power, but you really need to "see" the bad reading on the VOM to troubleshoot.

C5 Newb

I went through the diagnostic procedure for "wipers always on" in the service manual and according to the findings it says replace the motor.

I already replaced the motor & circuit board before BUT it was a cheap one....probably chinese made.

Since it runs, the "motor" probably is good right?

Maybe I need to change out the circuit board with an ACDelco one?

C5 Newb

With wiper switch off. key on I had the correct values at the motor plug.
Pin A had a good ground
Pin B had battery voltage
Pin C = 0
Pin D = 0
Pin E = 0

Pulled the circuit board off the motor and it had some water inside, the rubber shield / flap thing on top of the motor has a couple tears in it. I think when it rains (or car wash) a small amount of water runs down the shaft that goes to the wiper and gets inside the motor/circuit board.
I sealed up the tears in the rubber with permatex 1 minute gasket so water shouldn't be able to get into there again. Think maybe that was the issue all this time?
I would buy a new rubber piece but not sure where......

Lamarpro89

How were you able to remove just the button? I’ve searched a few threads on here and haven’t been able to read how people accomplished this. I have a new stalk to replace mine (sticky washer button) but would much rather swap the button rather than the whole stalk...thx!