One-way CAN BUS:It only get the original car ACC,lighting control,reversing and parking in order to achieve the audio controls operation of the original steering wheel. But it can’t exchange the information with the original car.
Two-way CAN BUS:It has the operation of the original car steering wheel buttons .  The car dashboard audio information also can be displayed. The below informations will be showed through the DVD/GPS:
the air conditioning system,smart remote control key
central control door locks,light systems,parking sensor settings
Commercioganic Features of our VW car DVD (HL-8785GB)
1.Novel and beautiful interface
2.two-way CAN BUS Configure
3.low price !!