A few years ago I tackled the window swith problem with no improvement. At that time it was a quick job except for adding the auto up mod! Disassemble, clean off the carbon with a light sanding, wipe with rubbing alcohol, then I made the mistake of putting dielectric grease in the contacts. It wasn't too long before the windows were inconsistent in their operation and over the months it became progressively worse to the point I had to disassemble again. The speed never really improved as it was always bad.
Recently I took it apart and found lots of black at the contacts and also the faces "burned" as one would expect from years of use. Unexpected was a bit of melting of plastic near the drivers up contacts. Things must have been warm at some point. Probably recently. I cleaned the contacts thoroughly with 320 grit sandpaper and/or red scotchbright until the black was gone.
I'm not an electrical engineer but I began researching how to prevent this flash and burned contacts and was directed at first to a RC snubber and then to a flyback diode. Studying the google content I tried my best to apply the arc suppression flyback diode to the circuits for the window motors. The schematic below shows what I believe represents a proper application of a flyback diode but like I said this isn't my forte and it might be wrong.
I had eight 1N4005 diodes in a bin. Soldering these in was a lengthy process but they did fit and everything went back together.
The window is now very fast, comparable to our 2009 sienna van actually in speed but a bit more grit in the window track by the sounds of it. All 4 windows move very nice except...
The drivers up doesn't work at all, down, auto up and auto down all work flawlessly. I'm hoping it is something to do with the melted plastic. Anyway I've taken the switch back out and will troubleshoot with a multimeter at first and then look at the schematic after that because my diode may interfere with the current sensing circuit possibly. Too late here to get into it any further.
If any electrical person can comment on the circuit it would be appreciated.
edit, checked the switch with a meter, no continuity drivers door 'up'. Will take it apart in the morning.
Recently I took it apart and found lots of black at the contacts and also the faces "burned" as one would expect from years of use. Unexpected was a bit of melting of plastic near the drivers up contacts. Things must have been warm at some point. Probably recently. I cleaned the contacts thoroughly with 320 grit sandpaper and/or red scotchbright until the black was gone.
I'm not an electrical engineer but I began researching how to prevent this flash and burned contacts and was directed at first to a RC snubber and then to a flyback diode. Studying the google content I tried my best to apply the arc suppression flyback diode to the circuits for the window motors. The schematic below shows what I believe represents a proper application of a flyback diode but like I said this isn't my forte and it might be wrong.
I had eight 1N4005 diodes in a bin. Soldering these in was a lengthy process but they did fit and everything went back together.
The window is now very fast, comparable to our 2009 sienna van actually in speed but a bit more grit in the window track by the sounds of it. All 4 windows move very nice except...
The drivers up doesn't work at all, down, auto up and auto down all work flawlessly. I'm hoping it is something to do with the melted plastic. Anyway I've taken the switch back out and will troubleshoot with a multimeter at first and then look at the schematic after that because my diode may interfere with the current sensing circuit possibly. Too late here to get into it any further.
If any electrical person can comment on the circuit it would be appreciated.
edit, checked the switch with a meter, no continuity drivers door 'up'. Will take it apart in the morning.
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