A couple of times in the last few months I've reached down to close the driver's window without looking and inadvertently hit the 4-way flasher switch instead of the window switch. When I activate the 4-way switch and then turn if off, my turn signals won't work. If I spray some electrical cleaner around the switch, the turn signals will start working again. Can anyone who has had the switch apart explain what is going on?

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13