Try removing the 206E module with the system powered off and disconnected from the AC. Power system back on with only 206 processor and check for steady green led on processor module and check for intercom dialtone at one or more of the extension jacks. If you have no dialtone it is the processor module. If you have dialtone power system down again and replace 206E module, power up system check for steady green led on both modules. If no dialtone now the problem is in the 206E expansion module. Be sure system is powered down and disconnected from AC before removing or replacing any modules. I have seen new modules that are defective.