We actually have an optional mod that enables the interface to power down with any surgery so such a thing does exist. Since this area appears limited to the scantool.net products I will elaborate further in the general OBD II forum.
We do not offer this as a standard product yet but when someone requests it as an option we are able to provide this capability...
oh man, i wish i new. i just bought an allinone from obdpros... works great by the way. i found out i need a maf sensor :)
1. Your talking about a device that uses <9mA...thats less then 1/4 of what most radios draw in standby. I leave mine plugged in 24/7 and the car has sat for weeks with only <1v of battery drop.
2. Someone could easily do a run of these devices wired the correct way and there would be no need for relays and other hacks. Most obd chips run at 5v...and so does your usb bus. So producing units that turned off with your computer would actually be cheaper to make. Of course once you factor in the $40 or so markup these guys put on no guarantee you'll see it. ;)
sorry mich! i really thought it was the same adapter. all these obd scanners look the same, its very confusing. i emailed the allinone people about my scanner though, im weighing the decision to sell this one i have and get the obdpro. we will see what they have to say first, they might convince me to just keep what i have.