I wrote a detailed post to Edmunds.com "Town Hall" S-10 and Maintenance Boards on this a year or so ago but can't find it any more! Since I see someone is looking for it here is the scoop:

Wiper Motor operation is intermittent - maybe associated with tempoerature under the hood or vibrations. The problem is the "delay control" circuit board inside the Wiper Motor. Defective solder-joints where the harness connector attaches to the board.

It can be fixed without removing the Wiper Motor from the vehicle (which is a real pain!). Just remove the cover from the wiper motor - the circuit board with the harness connector pops-out and, if you look at the solder-joints around the pins on the harness connector real close (like with a magnifying glass) you can see cracks in the solder around some of the pins. I re-heated the solder at each of the connector pins using a small soldering iron and flowed a little new solder into each joint. The wipers have worked fine now for over 2 years! If questions E-mail me ([email protected]) - I will try to dig-up my detailed instructions on this to post to the Edmunds Town Hall website again!

OK! I got a request for this from a guy in East Texas with the same problem - he said he paid $300 to his dealer to fix this once before, and with over 200k miles on his S-10 he wanted to try "the cheap fix"! Here it is, best as I can remember the details:

I have never found my original write-up on the s-10 wipers but I bet you have the same problem we did!

First off: you don't have to pull the wiper motor to fix this! Look carefully at the housing of the motor assembly and you will see that the cover comes off without removing the whole assembly. (I don't have the S-10 today at work or I'd take a couple digital pix for you. I think there is a snap or a couple small torx-head screws that hold the cover on - finding this is not rocket science so you should be able to manage it OK!)

Remove the cover from the Wiper Motor Assembly and the Control Board can be easily pulled-out - I think there is a connector going to the motor as well as the harness. Don't remember exactly what they are like but I think pretty much standard type connectors with some sort of tab you push to unlatch them. There might be another screw or two holding the board to the assembly too - take your time and make sure you have everything un-hooked so you don't need to "force" the board out of the assembly. I think it was tight fit in mine so it may "stick a little but it should pop right out with just a little light prying around the edges when it is ready to come out.

Once you get the circuit board in your hands you can look at the solder joints where the "header" for the harness connector is soldered to the board with a magnifying glass - bet you will find cracks in the solder around the one or more pins on the back-side of the connector header (these might only appear as a "gap" between the pin and surrounding solder - my biggest defects were on one of the end pins that was the power or ground connection to the harness, I think that was the one that was giving me the trouble)!

1.) IMPORTANT: Be careful not to let the board get "zapped" by static electricity or any of that East Texas lightning! Find a conductive surface to set it on when you put it down - don't set it on a piece of carpet or plastic, even a piece of bare sheet metal is better!

2.) Get a small soldering iron (the one I used had about a 1/8-inch tip on it - I don't know the wattage but it is a small unit!) and some fine flux-core electronic solder. Heat the iron 'til you can melt a tiny drop of solder on the end then touch the molten drop to the cracked solder around one of the connector pins on back side of the board and hold the iron there just long enough to see the solder on the board turn shiny and "flow" into the cracks/gaps - pull the iron away real quick after the solder gets "shiny" and wait for it to cool. (You are not really adding solder to the joint - there is probably enough there already! You are just "re-heating" it to get it to flow into the cracks or gaps better. The only reason for the drop of solder on your iron when you start is to make good thermal contact between the iron and the pins you are soldering. Heat flows better through molten solder than from a dry iron to a dry cold solder joint!)Look at the solder again with the magnifier - any cracks should be gone, if so you have fixed that pin (right around the pin the solder should actually form a "fillet" that kind of "climbs-up" the pin a little like a good weld joint)! I would also bet the solder around the pin you fixed will be shinier than when you started! (Dull-looking solder joints are a sign of "cold solder" which is a manufacturing defect and the reason that the board failed in the first place! If you look the board over you will see that the pins for the harness connector are the largest pins soldered to the board. They probably soldered the whole board in one automated process and did not heat the solder enough to make good joints on these large pins to avoid damaging the smaller components...)

NOTE: If your soldering iron is too big or you hold it on the solder joint too long you might get a brownish, burned appearance on the solder joint. This is not good but actually better than grayish dull-looking solder! Shoot for a nice shiny surface - that is your best solder job!

Because all the joints on the connector header on my wiper control board looked dull ("cold solder joints") I "reheated" the solder on every pin. Mine has worked for about 4 years now without any problems - I hope this fixes yours too!

You can then carefully re-install the board in the wiper assembly and plug-in the connectors and take some of the money you saved to treat your self to a good bowl of Texas chili to celebrate your accomplishment! (I'm a Yankee and I like beans in my chili, but no-bean Texas chili is good in a pinch!)

I'm sorry this set of instructions is a little vague - I did a lot better job when I had it fresh in my mind. I'll be darned if I'm gonna take it apart again, though, to remind myself of the particulars - "If it ain't broke, don't fix it!" is one of my mottoes!

Good luck and let me kow what you find and if the procedure works for you! (I have heard from 2 or 3 others who used this procedure to fix their wipers also, so I know my experience was not a fluke!)