Yep, they do different things depending on how long you hold each down... if I eremember correctly, if you hold the first one down for under a second, it'll start your car. If you hold both buttons down for like 2 seconds, it'll shut it off. If you have the door locks tied into the system, I think if you push second button alone it'll lock your doors.
Dunno, what all the different combinations are, just experiement for a few minutes.
btw: We have two command starts on two of vehicles and it seems the company went out of business. They even had a lifetime warranty, so you are screwed if you need another remote (my dad found out the hard way....

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