I personally wouldn't do it myself, but I'm generally disinclined to mess with anything electrical (beyond stereo stuff). Thing is, if tyhey short something out, they're on the hook for the repair.

I paid close to $300 (parts & labor & special lock interface) for remote start & lock/unlock all on one key fob

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo