There are 2 ways of doing this:

1. If there is not Autopilot the pins 10 and 11 on port A or B are the pins that when you connect them will trigger logging ***do not put power to either one of these pins*** just connect a circut. if your switch puts power out when activated go to radio shack and get a relay to close the circut. i can help you with the wiring if need be. once this is hooked up you will need to enable remote logging in the implement setup under the "extras" tab.

2. if there is autopilot then you have the option of applying power to one of the aux connectors, get ahold of me and i can show you how.