do you know how much voltage at keypad wire # 1220 protected powerProbably the best way to go about it is to get a DMM and start tracing back. Of course check your battery cables and grounds first, since that's where all power starts from.
There is a book for the 773 in the manual thread that has good wiring diagrams to help out.
I'm getting app 7voltsdo you know how much voltage at keypad wire # 1220 protected power