: wiper switch problem

02-23-09, 05:33 AM


my 1990 Brougham has a problem with the wiper switch.

I cannot turn the wiper off, while driving.

when I switch the ignition off, while driving, and then on again, it will switch off.

any suggestions ?




02-23-09, 10:14 AM
I'm not sure if replacing the wiper switch on a 90 Brougham is any different than on an 89, but on mine I just had to remove all of the screws that secured the wood grain trim panel that goes from the AC outlet to the right of the speedometer cluster. There is one screw in the AC outlet that you can get to with a long skinny philips screw driver. Once the screws are all out, the panel can be gently pulled away from the dash, and you can work a wrench behind it to get out the two bolts that hold the wiper switch to the dash.

That’s the easy part. The hard part is disconnecting the connector because it is under the switch, and if your hands are big it's kind of hard to get to. Then when the switch is unplugged, it just too big to fit between the dash and the panel, but it'll come out eventually.

Get a strong magnet in case you drop the bolts for the switch; they'll fall to the bottom of the panel and you have (I had) to use the magnet to get them to a gap in between the bottom of the trim panel and the dash.

02-23-09, 07:41 PM
I have the diagnostic and repair procedure for the windshield wiper circuit. The first thing you have to do is acquire a 12 volt test lamp.

The diagnostic and repair procedure is as follows: The following steps will be done with the ignition switch in the RUN position.
1. Turn the ignition switch to RUN and turn the wiper switch to OFF. If the wiper continue to move, continue.

2. Turn the wiper switch to DELAY. If the wipers delay between wipes, turn the switch to OFF and continue to step 3. If wipers do not delay between wipes, go to step 5.

3. Disconnect WIPER/WASHER ASSEMBLY (which is on the fire wall, in the engine compartment) connector C1 (which is to the driver's side of the assembly). Connect a test lamp from C1 cavity Y to cavity Z (I believe they go in alphabetical order from top to bottom). If the test lamp lights, leave the lest lamp connected and continue to step 4. If the lamp does not light, remove the washer pump assembly and check the park relay spring (I can give you the correct procedure if it comes to that).

4. With the wiper/washer switch OFF, disconnect the wiper/washer control connector (follow the procedure in post 1 to remove the switch, and the connector under it). If the test lamp goes out, replace the wiper switch. If the test lamp remains on, then the purple wire that runs from the switch to the assembly is shorted to ground and needs to be replaced.

5. Turn the WIPER/WASHER switch to OFF. Turn the IGNITION to OFF and back to RUN. If the wipers shut off and park correctly, continue to step 6. If the wipers do not shut off, continue to step 7.

6. Check holding switch for correct adjustment. If adjustment is required, adjust holding switch (I can give you the correct procedure if it comes to that). If adjustment is not required, replace timing circuit board assembly.

7. Check if washer override switch contacts are opened by projection on rim of ratchet gear. If the contacts are open, then the blue wire is shorted to ground and needs to be replaced. If the contacts are closed, then continue to step 8.

8. Check for loose timing circuit board attaching screw. If the screw is loose, tighten the screw and recheck washer override switch contacts. If the screw is not loose, adjust the washer override switch contacts or replace timing circuit board assembly.

I got all of this information from my OEM Cadillac factory service manual for my 89 Brougham, so the wire colors my be different. I recommend to you, and anyone who is considering repairing their own Cadillac, that they acquire a factory service manual. Here are a few service manuals on eBay for a 90 Brougham. (http://shop.ebay.com/?_from=R40&_trksid=m38.l1313&_nkw=1990+cadillac+brougham+service+manual&_sacat=See-All-Categories) (Good examples for you, but I'm sure eBay Europe will have a few good ones.)

02-24-09, 04:05 PM
I have found that if water gets in the relay it will keep running until it drys out.

03-01-09, 12:37 AM
I had the exact issue w/ my '88 Brougham. The service department said it was a bad "park switch" and printed circuit board. In my case it was not the control switch in the dash but components on the firewall of the engine bay.