Problem with Console Port

[Khurrum Shahzad]

Hi all ,   I am facing a problem with my  2501 router. It was working fine, but for the last two weeks I am not able to connect to the console port of the router. It shows nothing on the screen when I try to connect and press enter. When I checked the Signal level of the console port on my Break Out box, it showed me the continuous LOW status of TxD signal. When I reboot the router, it shows me the startup messages and finally after showing all those messages it  hangs and TAKES NO INPUT from the HYPER TERMINAL. I have also tried many terminal Software like Telix, Teraterm but response of the router remains the same. There is no problem in Console Cable as cable is working fine on other Routers. The router has no prior configurations (as I did an ERASE STARTUP CONFIGURATION before), so I am not able to connect via TELNET or AUX port. Before doing ERASE STARTUP CONFIGURATION, I was connecting to reouter with AUX Port and did my configuration but after erase NVRAM, AUX was shut and router becomes useless. Is there any way out??? Can I replace NVRAM of this router with any other NVRAM having configuration and then connect with the router with AUX port or via TELNET? Is NVRAM Of 2501 router replaceable?   Please help me if anybody has the solution.   Khurrum