We All Love Pretty LEDs...dont we?

you can get different volt led's I also changed to a blue led some time ago and had the same problem so i used a smaller voltage led from radio shack. i also used a resistor so the alarm wouldn't "burn it"

I had no trouble at all replacing the red led with a blue flashing led from varad. My alarm is a Python 1500. At first I used the ground when armed output but I didn't like it because it didn't show system status anymore, instead it just blinked when the alarm was armed. So I cut off the red led and the flasher that is wired to the blue led. I then just wired the blue led directly to the wires that were powering the red led. It's been working for about 6 months perfectly with no problems at all. Just be careful, as it may cause trouble with other alarms.

you gotta remeber that LEDs are not voltage driven devices (like incandesent lightbulbs), and therefore need a current limiting resistor in line, Unless the manufacturer already put one in like those 12V LEDs.