You may have damaged the alarm module when you jump started the car. I hope I'm wrong.
I damaged mine (in my '90 300CE) when I gave someone a jump start. Shortly after the good samaritan act the alarm would go off for no apparent reason. I checked out all of the door switches etc. but everything looked OK. So I bit the bullet and took it to the dealer who replaced a fried alarm module. (about $ 400 as I remember)
That was the last jump start I will ever give with a Benz.

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1990 300CE-24 (Gone but not forgotten)
2002 SLK 32 AMG
2002 ML320 (Gone)
1995 E320 Cabriolet