Batboard

A friend gave me a NOS 30 watt MCS to program on 900 ham freq's. 902/927. I was the first to program it since it left the factory, & it worked fine for a year. Suddenly, the display showed fl 01/82. No one has ever tried to program the radio since I set it up, but the 12 volt wiring was a bad joke. Thin wire from a CB powered the radio, with black tape covering twisted cables with no solder. I can read the radio, make changes & write to it, but it still shows FL 01/82. When I read the radio, the laptop shows "block checksum failed for vector for external radio blk block. continue unpack anyway? I click yes, & the screen opens ready to program. Looking in the MCS section, fl 01/82 says e-prom checksum error. bad external checksum error. What does this mean? I don't know what he did to the radio, & it worked great, & one day it died, but no one tried to program it. He gave me the radio & gave up on 900. Thanks. GARY