When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So , my delay wipers weren't working . The exact symptom was that the regular speeds worked fine , the wipers would properly park themselves when shut off , but in the delay mode the wipers would rise up from the parked position into the waiting to sweep position like they should , but then would never sweep . The wiper switch and the variable resistor checked out fine . So I took the cover off of the wiper motor , removed the very delicate spring clip holding the black round switch actuator on and removed it , and then unclipped the board out of the outer case (it holds in on two molded in plastic catches , one of them you can see at the very top of my first picture)) . There are four transistors (Motorola M8467) on the board whose numbers come back as unobtainable from my local electronics supply house so I had to pray it wasn't any of them , I really wasn't up for chasing down some close enough substitutes . There are three diodes which the diode check function of a modern digital meter verified as good . The two relays similarly checked out fine (good coil resistance and clean not burnt/pitted contacts) as well as the two switches , S1 and S2 , their contacts looked great . There are a handful of resistors that all looked OK and indicated close enough to proper resistance , so then the final parts roundup brought us to the four capacitors . Their values were 220MF @ 10V , 15MF @ 25V , 10MF @ 50V , and 4.7MF @ 35V . My local electronics supply store did have pretty much what I needed with the exception of the 15MF which a 22MF was the closest they had , the new values being 220MF @ 25V , 22MF @ 25V , 10MF @ 100V , and 4.7MF @ 100 . These four capacitors cost a grand total of $2.82 and lo and behold when I installed them and reinstalled the board the delay wipers now work ! A close look at my second photo shows where capacitor C3 appears to have leaked out it's goo (electrolytic paste , it's the cloudy looking stuff covering the label for R9 and running under R7 and R8) and was likely the only one that was actually bad . Now just so you know , the values not being 100% exact are OK , with capacitors you can always go higher on the working voltage with no problem whatsoever , you just can never EVER go lower on the working voltage as the poor capacitor is then being operated above it's max working voltage , they usually pop open (sometimes really loudly) and spew electrolytic capacitor goo all over the place when asked to tolerate more voltage than their rated for . As to the actual capacitance , the working tolerance on electrolytic capacitors is usually quite high , sometimes on the order of +100% / - 50% , so the 22MF substitution for the 15MF is fine and well within standard tolerance norms . Anyway , it works again and I hope I've given some of you electronics minded people the info you need to fix yours (if your symptom is the same , that is)
If any of you have any questions feel free to ask ...........
Last edited by OrangeBird; 10-17-2020 at 07:54 PM.
You actually still have a real brick-and-mortar electronics store in your area ??? Even Radio Shack is gone around here (CT).
Nice fix.
Thank You .
And yes indeed and I am thankful for it every time I go there ! What they are particularly great for is having both modern and vintage components , Vacuum tube type components included .
How do they stay in business? Not many people try to fix anything anymore.
They are around 30 miles from Boston and have been the area's electronics hobbyist's mecca for years . Since today is Saturday there was a pretty good number of customers when I was there , akin to an average supermarket crowd on any given weekend day . There are others around as well , just not as close to me (I happen to live around 40 miles from Boston) but "You Do It Electronics" is by far the best stocked so I always go there
Good job. I used to fix computer motherboards, mostly Dells, and there was one model that the whole line of capacitors on the board would fail when they got older. The can would bulge at the end, the tell tale sign, and 9/10 it would fix the problem
Thank You Scooter , It would appear that capacitors are the bane of electronics , both modern and vintage . I restore antique tube radios from the 1920s through the 1950s and the old caps are SO bad it's common in the hobby to "shotgun" replace every cap in a newly found set before powering it up (radio hobbyists call this a "recap") . The old caps usually die shorted instead of open , then when powered up they draw destructive amounts of current through other associated circuit components like RF coils and the like which can be impossible to find replacements for . Sometimes when dealing with a particularly valuable radio where looks count and not wanting to ruin the original look of the chassis an old capacitor will get gutted and a new cap installed in the old case . This was a three section old power supply filter cap that I restuffed with three modern replacements to preserve the original look .
You can also order all kinds of capacitors and other electronic components from Digikey, Mouser (who carries the full line of Aptiv connectors as well), Jameco, etc.
Electrolytic capacitors have ratings in ripple current, effective series resistance, °C, and hours of lifetime, as well as their capacitance and voltage. Nowadays there are ones specifically qualified for automotive use... considering that in an auto they have to function from -40°F to 200°F, whereas ones for home or even industrial electronics don't cover anywhere near that range. That qualification is called AEC-Q200 (for passives... the same organization publishes others for active components). It didn't exist in the 80s; which is probably why so many of them fail so much. Interestingly, one of the main criteria is vibration and shock resistance; something that home or commercial electronics hardly ever have to face.
I would STRONGLY recommend that Q200 parts be used for this. Otherwise in a year or 2 you'll be right back to where you started all over again.
Here's a link to Digikey for example, filtered for AEC-Q200, automotive, polarized, and through-hole. Check out the range of hours vs temp ratings that are available in that group.
Thanks for the write-up, I'm sure we'll all need to be doing this at some point. Funny you posted this, yesterday wife and I were driving in her car in a misty rain, and the damn sensor wasn't working like it should. I said to her, what ever happened to the good old delay wipers. She said, now your sounding old, I replied, hey, at least they actually work!
Sofa makes a great point about using the best rated parts for longevity . I had thought of ordering the caps on line but that would have meant having no wipers till they showed up . This being a daily driver my thought was that if the off the shelf caps live even half as long as the originals did , it'll very likely be longer than I'll be driving it . If they die sooner than I do , well then I'm already well practiced in their replacement
Interestingly, one of the main criteria is vibration and shock resistance; something that home or commercial electronics hardly ever have to face.
And now that I've agreed with you about the wisdom of the best rated components for maximum longevity , as a point of conversation I gotta ask , do you think the underhood high temperature of a car gets that much hotter than the internals of my first pic when it's mounted in it's cabinet ? And surely whats in my second pic vibrates more than anything bolted to the body of my car , hopefully ? Not needling here , I'm just truly curious which really is the worst environment for our poor capacitors to endure ? The car wins 100% in the widely varying temperature conditions capacitor torture test for sure , but tube amps , especially high powered ones , are known all too well for pushing the design limits of their components , tubes and capacitors especially , to produce "That Tube Sound" that still has a huge following today .
Last edited by OrangeBird; 10-18-2020 at 02:51 PM.
back in the day, there used to be a Mil-grade spec. these were the toughest. You had to look for these when designing. Then, we went COT. Somehow, airplanes, tanks other machines that operated in extreme conditions were way overrated. I guess?
There are too many " MIL specs" for anybody but the professionals in that area to know what they're doing.
I have a US rifle mfd in 1943. (yeah, it's a shooter, not a looker, not a collector, I can put a whole clip into a pattern about the size of a quarter with it) There's a "MIL spec" grease for it. People get on the message boards and ask "where can I get such and such MIL spec grease". Turns out, the ONLY thing in that spec is, salt water wash-out; and, ANY modern automotive grease, is AT LEAST 5 times better than that spec. Everybody uses Mobil1 which is like 20 times better than "spec", unofficially. Hasn't been submitted to that specific test battery. Butt... it isn't qualified as "spec". So, is it good enough?
Bottom line is, "MIL spec" is complicated. If you don't pay attention to the details it does no good.
Good God I'm SO glad there wasn't such powerful angry rock as the song "We're not gonna take it" when I was young , I might still be doing time ! Although I was a bit old for that kind of music by the time Twisted Sister came about I always really liked the raw energy of the heavy metal hair bands like TS . Interestingly , Dee Snider (the man pictured here , the lead singer of TS) hosts syndicated a radio program called "The house of hair" on my local rock station on Saturday nights , although I coulda done without the drag queen thing the music was awesome and perfectly defined the 1980s for me
There are too many " MIL specs" for anybody but the professionals in that area to know what they're doing.
The electronics had a wider band of temperature operation range and able to survive nuke EMP, I don't know, maybe they still have it, but it seem to be less common for sure.
Good God I'm SO glad there wasn't such powerful angry rock as the song "We're not gonna take it" when I was young , I might still be doing time ! Although I was a bit old for that kind of music by the time Twisted Sister came about I always really liked the raw energy of the heavy metal hair bands like TS . Interestingly , Dee Snider (the man pictured here , the lead singer of TS) hosts syndicated a radio program called "The house of hair" on my local rock station on Saturday nights , although I coulda done without the drag queen thing the music was awesome and perfectly defined the 1980s for me
One last thought on this: despite the drag queen looks of the 80's hair metal bands, and how most people would stereotype him in with all the other drug-abusing burnouts, Dee Snider was sober and he kicked a$$ at the PMRC hearings. They didn't expect him at all. He is very intelligent and I am still amazed when I listen to old Twisted Sister music. You are lucky to be able to tune into his radio show on your local station. My stations keep playing the same songs that I have heard for the past 40 years over and over and over.............
Back to your regularly scheduled program.
One last thought on this: despite the drag queen looks of the 80's hair metal bands, and how most people would stereotype him in with all the other drug-abusing burnouts, Dee Snider was sober and he kicked a$$ at the PMRC hearings. They didn't expect him at all. He is very intelligent and I am still amazed when I listen to old Twisted Sister music. You are lucky to be able to tune into his radio show on your local station. My stations keep playing the same songs that I have heard for the past 40 years over and over and over.............
Back to your regularly scheduled program.
OMg that's incredible yoiu can do that stuff......this is wifes car so..... to gd things work only a a little bit start upfine only go up aq bit then it;s back and forth only at the bottom just keep; going baqk and forth ,,,,taken everything apart no cluell
You actually still have a real brick-and-mortar electronics store in your area ??? Even Radio Shack is gone around here (CT).
Nice fix.
You don't have a Micro-Center anywhere near you in CT...
But if you drive down towards the South West Border (NYC) there are like 6 in the area.
Google Maps shows that the Closest location to you (which is the one I usually use) is Yonkers, NY...
It shows almost 2 hours of driving... BUT THAT MUST BE WRONG
I used to drive from that part of NY up The Merritt CT-15 to Springfield, MA in 1 Hour 45 Min.
Last edited by vorteciroc; 07-03-2023 at 02:19 PM.
10-17-2020, 06:01 PM
A close look at my second photo shows where capacitor C3 appears to have leaked out it's goo (electrolytic paste , it's the cloudy looking stuff covering the label for R9 and running under R7 and R8) and was likely the only one that was actually bad . Now just so you know , the values not being 100% exact are OK , with capacitors you can always go higher on the working voltage with no problem whatsoever , you just can never EVER go lower on the working voltage as the poor capacitor is then being operated above it's max working voltage , they usually pop open (sometimes really loudly) and spew electrolytic capacitor goo all over the place when asked to tolerate more voltage than their rated for . As to the actual capacitance , the working tolerance on electrolytic capacitors is usually quite high , sometimes on the order of +100% / - 50% , so the 22MF substitution for the 15MF is fine and well within standard tolerance norms . Anyway , it works again and I hope I've given some of you electronics minded people the info you need to fix yours (if your symptom is the same , that is)
Even Radio Shack is gone around here (CT).
Thank You .
And now that I've agreed with you about the wisdom of the best rated components for maximum longevity , as a point of conversation I gotta ask , do you think the underhood high temperature of a car gets that much hotter than the internals of my first pic when it's mounted in it's cabinet ? And surely whats in my second pic vibrates more than anything bolted to the body of my car , hopefully ? Not needling here , I'm just truly curious which really is the worst environment for our poor capacitors to endure ? The car wins 100% in the widely varying temperature conditions capacitor torture test for sure , but tube amps , especially high powered ones , are known all too well for pushing the design limits of their components , tubes and capacitors especially , to produce "That Tube Sound" that still has a huge following today .
