I purchased 2 "budget" bluetooth OBD2 adapters which I have been disappointed with. I originally read this post about 6 months ago when I was having problems just after receiving them. I have tested these adapters out on at least 6 different vehicles. The only vehicle I have gotten both adapters to work on was a 2002 Kia Sportage (Hyundai). And with all software functionality. I am wondering if in particular parts of Asia where these are manufactured that they are using a different type of OBD2 compatibility than what our made-for-America vehicles are using? I don't have enough experience in that department to really know. I've had this adapter connect to every PC and mobile device via Bluetooth fine but when the ELM327 software is attempting to use all the protocols available, it is unable to connect to a Ford, Chrysler, or Chevrolet vehicle.

My adapters MAC address does not match the defective MAC listed in the original post. 

Here's a few photos of my adapter(s). I did a quick tear down of the device. I compared the adapter teeth to my OBD2 scanner cable connector (which connects fine). The teeth in this adapter appear to be more recessed. They are also soldered in at such different lengths that perhaps there is a bad connection to the ECM when plugged in to most vehicles? Just a thought for those that have no functionality on their faulty or perhaps intentionally faulty Bluetooth adapters.

Update:

I took a look at the diagrams for the OBD2 pin configurations on typical OBD2 connectors. If anyone is interested, this unit is lacking pin #2 (J1850 Bus +) and pin #10 (J1850 Bus). It looks like several pins on OBD2 connectors are left for manufacturer specific features. This unit does not have any of those additional pins, as well as support for J1850, (assuming that I read the pin diagram properly). But if you read the case on the adapter, it "supports all OBD2 protocols"! SAE J1850 is listed as being used "mainly by US manufacturers". My assumption over these cheap adapters is that they were manufactured for the Asian or European vehicles in mind, hence the lack of the J1850 bus pins.

The pins that are present on my adapters; 4, 5, 6, 7, 8, 14, 15, and 16. Here's a chart for the OBD2 pin out configuration if you feel the need to pull your adapter apart to see what bus it supports. This is the car side of the adapter so you'll have to look at your pins in reverse.