Hello, I have a cv906 that I bought for my small 10 truck fleet, however it won't read half my trucks. It has read them in the past but took hoursnto get it to read and I don't even know how I did it. Now it will not connect at all. It is not an obd problem as i can connect with a cheap crummy code reader. I just updated the unit and no change. How do I get this fixed? Thank you

Tags: cv906 , problems , wont , read , vehicle