I bought this unit, and it really handy. I seen s few people posted here they cannot read codes from certain engines or manufacturers. You need to make sure you are using the correct protocol. J1939 will not work with many manufacturers, Play with the unit and protocols, and I bet the unit will work fine. I gave it 4 stars because I can only graph one data stream at a time and not 4 like the say.
The unit has read all of my Cummins and Cat engines with no problems. It has also read my Merritor Wabco and Bendix anti lock brake codes and data streams. I have a Eaton auto-shift transmission in one of our trucks. I switched the protocol, and was able to read and clear codes, along with the data stream for the input and output shaft speed sensors. Pretty handy for the price.
Will not read Volvo cab, body or climate codes. But for the price, not too bad.

thank you for the product. it is easy to use and diagnostic the vehicle. I like the free frame. make everything look easy.

For the price one of the best products on the market. Easy to use.

Hi,can i add obdII in this when u update it? i cant use it in ford expedition? why is it?tks for your help.