08 outback seatbelt sensor

I have installed a gps tracking unit into this car. the unit also has 2 inputs for monitoring (low inputs) and 2 outputs for whatever. I used one for starter kill and the other for door unlock. this is all done remotely via the web. OK here's my question. The customer wants to monitor when the seatbelt is on. sounds easy enough, but after testing the two wires it is not a simple switch. I am going back on friday to hopefully complete this. I tested my vehicle today and took the seatbelt apart. I discovered a resistor. The ecu seems to be monitoring for a change in resistance (1 ohm). How can I get a useable output to triger a relay from this?

nevermind................i am an idiot!