Pixhawk aborts flight after Sonar Installation


Im having issues with my Pixhawk aborting flights after installing a Maxbotix analog sonar rangefinder. Ive set it up via the instructions in the Copter 3.2 wiki, and also set it to be used till 60% of the sensor reading, at which point it should change to Baro.

But when I take off, it goes up a couple meters, the Sonarrange reading goes from .25(sitting on the ground) to .3 then .4, and about that time, the drone lands, no matter how much throttle I give it. I dont get any error messages or failsafe messages. But upon takeoff, the altitude reading in the quick section goes negative as I go up, which it didnt do before installing the sonar.

I cant seem to figure out why its landing, and why the altitude measurement is negative. Any help would be very appreciated!