very nice information, explains the complete central chassis system.
The EDC info is from EDC I, not EDC III, which were both used on E32.
EDC III from around summer 1990, depending on countries. But EDC was always optional extra.
http://pok.atw.hu/index_elemei/home_elemei/letoltes_elemei/EDC%20-%20Central%20Chassis%20Electronics.pdf

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