does it disable the horn alert when opened?
if it does they can gain access without alerting anyone and get access to the obd.
i think one of the issues we are starting to see is the availability of programming tools online cheap, the same tools locksmiths etc use so they can use the same methods to access the vehicles computer and reprogram keys like a locksmith would do.
the only hurdle i could see is when they open the door the horn will go off so if they can get around that using a pkes sniffer then they can get access to what they need.
another thing they could do is if they know the wiring system enough they might be able to isolate a canbus wire externally and if they can do that then they could unlock the vehicle and enter without the horn sounding.
if they are using obd programming tools then one option is to remove the standard obd port and replace it with something non standard then make a patch cable from that to obd so when needed it can still be accessed by standard programming tools, while they could try and make a patch on the go they would need spare wire and time to do it.
3rd party isolation is the best imo because its not standard so they dont know what they are looking for which is why we use the gtk devices on the mine/refinery sites, once disabled the vehicle is not going anywhere and if it moves(towed) we get alerts.
that starterstopper thing is a pretty good idea, like i mentioned before it can be spliced into any electrical line for isolation if you use/make a latching relay.
its getting to the point where it was harder to steal on old 1980's corolla then it is to steal a modern vehicle with advanced security systems, just look at that kia usb garbage LOL
