https://pinside.com/pinball/forum/topic/fixing-a-dead-dmd-column-or-row-cherry-4205-dmd describes one way. Ask cfh or borygard ltg barakandl why they are not typically repaired.
Quoted from ccbiggsoo7:
sometimes they can, but time you pay somebody to do it, its cheaper to buy a nice used one for $100 on here. see them daily with all the color dmd replacements.
Not impossible to find but comparatively very rare.
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