The Sega CD1 has a bunch of electrolytic capacitors that leak all over the internal circuit boards resulting in traces and vias no longer making electrical connections and render the drive in-operational.  We've successfully restored dozens of these devices to working condition.

A comprehensive repair includes the following:

• remove all the old electrolytic capacitors
• clean / restore the capacitor landings
• fix any broken traces / vias 
• electrolytic capacitors will be replaced by high quality Japanese brand (Nichicon, Panasonic, Rubycon, ...)
• replace the optical drive belt if required
• replace the 7805 voltage regulators, fuses and other components as required
• system cleanup and verification