I recently had to recover my 7941 from this type of failure, here are my procedures: You cannot break the Phone anymore than you already have, so what the heck.
Materials Needed: old cisco rollover cable or one you don't mind converting
RJ-11 molex, Crimpers, Scissors and knife
Cisco Power brick or POE switch you can VLAN off for a private laptop to IP phone network
Cisco Phone loads for your IP-PHONE that is no booting or you reset to factory defaults.. and is a brick at this point.
Small HUB or Switch (could be same your using above to power on the phone?)
Create a roll-over to aux port cable:
1. Use RJ-11 Cisco Roll-Over Cable
PIN 2 = RED wire PIN 4
PIN 3 = Green wire PIN 5
PIN 4 = Yellow wire PIN 6
Remove the remaining wires as you will not need these and they get in the way when you try and crimp the RJ-11 molex.
User the standard COM settings you would use to console into a cisco device:
COM (x)
9600 Baud
8
N
Plug the RJ-11 into the AUX port on the back of your IP-Phone and DB-9 (female) end into your laptop or PC. Bring up your favorite Terminal emulator with the above Console port configurations.
Create a TFTP Server and DHCP Server on your laptop (PC)
2: Download and install TFTpd32 http://tftpd32.jounin.net/ (I use this because it has the built in DHCP server with options as well) you can however use what TFTP app you wish as long as you can create a dhcp server from your machine not connect to the Corp or internal network.. Our goal is to use your laptop as the TFTP server for the phone loads to come from.
Configure a DHCP Server Scope
Use whatever IP scheme you want I used : 192.168.1.2 - 192.168.1.250 255.255.255.0
Set Option 66 with the IP address of the computer your using... I set my laptop IP as the first useable IP in the DHCP range that I created with TFTpd32 such as 192.168.1.1
Ensure you disconnect your local ethernet connection, and Set your IP address to 192.168.1.1 255.255.255.0
Unzip the Phone loads for the Phone you are trying to work with into a folder. Using your TFTpd32 server ensure you are pointing to the Cisco Phone loads folder you just unzipped.
Create your own little Network
3. Use a small switch or hub to connect your laptop (PC), and connect your IP Phone to the same small hub or switch ( you will need a power-brick) to power your phone. If you have an extra POE switch laying around or your feel comfortable vlan-ing off a switch to allow your laptop to IP-PHONE network to run go ahead and do it.
Plug in your phone to ensure that you are getting Power: If and when you get power watch your Terminal emulator Console session and you should see that the phone boots and runs trough a power on self test and broadcast for a dhcp server... Watch the TFTPd32 application DHCP Server and you should see that it provides an IP to your phone. If you have the Console window and the TFTP server window next to one another you can see that the IP Phone will get an IP address and TFTP server address.
The IP Phone will run through the nornal attempts to load the firmware, load image files and such. This process with take about 3-5 minutes and will reboot several times before coming operational. Once the Phone comes to the point where you see that it is attempting to register you can disconnect it from your private little network and plug it back into production and walk away smiling.
Good luck, and happy hunting.
Joe Sanchez
CCNP,CCSP,CCIP (Friendly Engineer)
