I thank you so much for posting this!
It hasn't been a priority for me to fix mine, I at least have the 'mist' position for a single pass (since I added intermittent wipers), and I live in the desert.
I hadn't opened one of the modules yet (I am an electronics nerd by trade, for anyone that hadn't noticed), and I had no idea there was was an Integrated Circuit in the module. GM had been fond of using a completely analog designs (everything on this board except the IC) on other car lines.
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Even my Caprice with the concealed wipers, and ungodly complex wiper motor with intermittent, has a little analog board. Just found out this week even Cardone has given up on their CRAP rebuilds of those.
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I had to look up the IC to see it's function. Can't remember after all these years, and only old guys like me would have ever remembered this old series of basic logic ICs.
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Interestingly too, they used an SCR (acting like a higher power transistor) to trigger the wiper motor rather than tripping a relay (like my car, under the hood), that would have caused an audible 'click' in the interior (like my stupid Ford) with the start of each intermittent sweep.
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