I am using a Modicon Gould 984 PLC. The PLC will not communicate and I have replaced the CPU one time in the past. I received a rebuilt CPU, plugged it in and when I went to connect, it said PLC in dim awareness mode. It gave me the option to cancel, 584 or other. I tried other and it gave me a communications timeout error. When I try to connect again it just gives me a communications timeout. I received a second CPU and it gives me the same results. Any suggestions???