Samsung PLC N-70plus CPU CPL9215A

Dear,

I got few numbers of this Samsung PLC CPU (N-70plus CPL9215A) cannot work in good condition (used in Loader machine). The "COMM" light is Turn ON (Green) but the "RUN" Mode Light not Turnning ON when i plug into the PLC Base Plate. After i had chaged the IC Chip 29EE512 90-4C-PH inside the CPU, but the condition still remains the same. Some one told me the program of the CPU is gone, but how could i ensure the program is not in the CPU. I also looked through the Samsung PLC website, but all in Korean words. Can anyone help me?

Thanks/Tony