Shame. Back in the day (way back, I guess), there were individuals and shops that would have had the skills and tools to repair such modules or their equivalents from the period.
In the old days shops thrived doing repairs on things like alternators, regulators and starters. Nowadays people just junk their old stuff and replace it with new; remans are available only from big conglomerates for simple stuff from brake calipers or alternators.
Manufacturers don't help; they mark the semiconductors in their modules with proprietary numbers that are meaningless outside the OEM, they provide no schematics (unlike, say, older TVs and stereo systems where manufacturers made schematics available for purchase...) Manufacturers have you by the balls; by making their modules so secretive they're all but unrepairable and you're forced to buy new or forage junk piles for replacements.