There is a SLK / Crossfire specific forum somewhere on the net, try posting there and here in parallel. Be sure to post results.

The Chinese systems are made by a bunch of companies so I don't have a recommendation. Don't use it on a computer that you are using for other things and never hook it to the internet, it will phone home and "brick". ( be sure to shut off the computers wi fi and also pull the wi fi card from the scanner. )

From other posts I read, a CAN module is staying awake drawing power. ( Controller Area Network ) these modules are throughout the car and control various functions over a 2 wire communications network rather than having a bunch of wires for each function.