I bought an Innova OBD2 reader some years ago. Not the cheapest, but not the most expensive. It's been good for reading basic stuff and resetting the codes.
But, I'm not happy with it. It can't read all codes. Innova has a website where you can download software updates and manufacturer extensions, but the cost is prohibitive.
When a error appeared on out Toyota, the reader did not recognise the code as it had to do with the seat belt system - a Toyota exclusive code. Never did figure out what was wrong.
When an error appeared on our Acura, again, the reader did not recognise the code. The dealer charged me $150 to tell me that a solenoid was acting up in the rear axle. It was a known problem with Acura and Honda AWD models. I found detailed instructions on the 'net on how to replace the solenoid.
