If the EC2 and EM2 are not talking (also indicated by blinking NOP) then the EM2 will not get the fuel maps from the EC2.  Therefore, you will see a flat line on the EM2 even though the EC2 is just fine. 

If the correction table is flat at zeros, it is because Tracy clears it when doing an update (been there, done that more than once).  If the EM2 is not reading the EC2 table it will be flat at the bottom of the scale (-127).

Al