I'd start with relays or fuses on the alarm itself.

I'd also take it to the shop that did it and explain to them what it did and have them look at it.

Alon

__________________
'92 300CE - Sold
2004 C240 - 744 - C7 Wheels - Android Radio
2002 C320 - 816 - Sport Wagon - Sold
2006 E350 Wagon - 368 - Dead
2015 GL350 Bluetec - 197U