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New Member

Dead 3640 after a flash upgrade

I "managed" to brick my old Cisco 3640 : a friend of mine give me 2 flash simms from an old 3660. I've tried to boot mine with those two simms but it didn't boot : the system led is continuous flashing. I've tried back to boot it with the old simm (16MB) but the same behavior : the system led is flashing endless. If I connect the console cable to router it doesn't show anything.
What should I try? is any hope to "unbrick" it?
Thanks in advance.

Later edit : if I press any key into the terminal, I see a lot of strange characters, something like this :

"ù)Äøöúµ üùJÆÿ¤þñèmóè´ÿyic×þ´ÿùJÆÿðþ𠡤þ"

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Re: Dead 3640 after a flash upgrade

Strange / garbled characters sometimes mean a baud rate mismatch. Try adjusting it to different values.

Assuming your straighten out the console, try booting with no flash installed and post the results.

New Member

Re: Dead 3640 after a flash upgrade

When I saw that strange string, my first thought was : serial baundrate mismatch. I've checked and rechecked the serial settings, I even try with another serial2USB cable, I've changed the console cable. The only think that I didn't chanced was the laptop. With all this changes, nothing happened : same strange string (only when I hit a key on my keyboard).
I've tried to boot up the router without flash simms : same behavior (nothing returns to terminal emulator just strange characters when I press a key).
I will try to connect to the router using my desktop computer which has a serial port and see if something is changing.
Thanks alot for your replay

New Member

Re: Dead 3640 after a flash upgrade


   just check console bit per second and change this value one by one.if not work then remove flash and DRAM again insert it and try again.

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