My dealer gives me a break sometimes, and quoted me $60 to do so. I accidentally set mine off removing the harness from the gauge cluster on the SL500 trying to replace bulbs.

I've heard quotes anywhere from $60 - $80...

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car