Question:
How to find the password for many Simplex fire alarm panels like 4020 4100

Answer: A quick and easy hack that I learned while working on many simplex fire alarm systems when I did not have a password to put the system in bypass etc. This will work on all Simplex panels that save there program changes to a file on a floppy disk that the tech leaves in the panel. Systems like 4100, 4020, 4120. Find that diskette and on it should be a file named after the panel serial number and DBF as the last three letters.

( Example : 12345678.DBF )

Make sure the long number matches the serial number on the metal fold down flap that covers the main panel control keys. What you need to do is load that file on a computer and open it with a program like hexedit that allows you to look and search binary files. After you open the file with your hexedit, do a search for the string 222. The reason you need to look for this string is that these systems always have a default level 2 password of 222 that can't be changed ( learned through a conversation with a simplex tech). Somewhere in there, next to a 222 string should be the other passwords for the other levels, including level 3 and 4. Also note that there might be several places in the file with a 222 string, so you will have to find the all of them and find the one next to the passwords. I have used this techniuqe on 10 Simplex systems so far and it has not failed me yet. Although it has pissed off the simplex tech because he can't figure out how I get his new password on one system that I work on. Also note this will not allow you to make "program changes" because you would need simplex software and a computer to do this. This will only allow you to disable control and monitor points and use the disable keys usually programmed on the left. I also found out that level 4 will not get you anything extra that I can tell, other then leaving the system in troube requiring a system warm start.