Stereo & Electronics - Lost Alarm Remote

what happens if you lose it and the car's alarm is armed?

will the spare chipped key disarm it once in the ignition and cranked?

then later, how do you turn the alarm back on?

The chiped key should shut if off. Alarm can be re-activated by using the door lock when you get out, this is how I set mine all the time. No need to be blowing the horn just because you set the alarm.

Yup, put the key in and turn the ignition on... that should do the trick...