Get alarm to honk or flash lights when locked
 

When I lock the car with the remote, I can hardly tell the thing is locked. Is it supposed to chirp the horn or flash lights? I checked the manual and it doesn't seem it should but how else are you supposed to confirm other than listening for the mechanism itself or checking door handles?

There is a section in the owners manual that covers this. The turn signals flash twice when locked and once when unlocked. Locking twice is suppose to beep the horn. My system appears to have some issues and I've never heard the horn honk for anything related to the alarm system.

Yeah Really? I read in the manual that a double lock disables the interior sensors. That DOES produce a short honk though. Maybe I need to look for the turn signal flash.

Also...
 

...if you hit the button once, and you get a honk, that means the interior console is not shut or a trunk or frunk is not shut.

I might also add that when it happened to me it was right after I replaced my factory radio/gps with an after market system that wasn't grounded properly. The horn made a chirp when it shouldn't and the led on the dash went into double blink mode when it shouldn't. Took it back in and got the problem corrected. Now it's back to normal...push the button on the key fob, turn signals and tail lights blink twice followed by the led on the dash blinking 21 times fast then a slow blink every 2 seconds after that and no horn at any time.

That is how my SE reacts to a double lock. One push is everything alarm wise enabled accompanied by a double flash, no horn honk. Double lock disables interior sensors + horn honk to warn you (that it disabled the interior sensors)

This is accurate, thanks. I realized the double flash does exist - it just takes a second, unlike my daily driven BMW which has conditioned me to expect it instantaneously.

Here's the info on page 22 of the pdf manual I have access to. Don't have my printed manual with me at the moment. I guess different years may have different setups. Mine is a 98. There's a bunch of different modern the central locking section of the manual.