Was there a battery left in the Saturn for a long time that caused corrosion to the battery contacts? You should try cleaning the battery holder and if you have a multimeter, check if the SRAM is actually receiving the 3v from the battery.
+1. Also, the Saturn schematics have been dumped, you can find them on NFG games / GameSX. For about $5 you should be able to replace the SRAM chip if needed. If you get desperate, I might be able to send you one from a broken PCB.