Hey all, just wanted to bump this as I'm experiencing the same problem.
Just installed an M80s to my S13 and liked the bonus of a built-in timer but I can't get mine to work either.
I made sure that IGN was going to the 1st set of contacts and that the ignition sense wire was connected before the cut but I still can't get it to work.
I've gone into the programming options and set the timer for 1 minute (down from 2 from factory) and hit button 3 while the ignition was on and got the single chirp to confirm it was active but the ignition still turns off right away with the key.
Even tried hitting button 3 to get 2 chirps incase it was a misprint in the manual but still, no dice.