Hi Guys, this is going to sound like a dumb question, but I'm going to ask it anyway. I'm running a ScanTool OBDLink LX bluetooth dongle and using the OBDLink app on my android phone to monitor engine vitals. My mechanic said that OBDII dongles can mess with the OBD system and prevent it from registering a fault code and displaying the Check Engine Light. This sounds unlikely, but does anyone who knows more about OBDII than I do think there's anything to this claim?

 

they can reset codes but should only when commanded to do so. Other wise it's just receiving data, not sending.

Now my can tool hooks to the obd but that is a whole different animal.

 

Your mechanic is trying to safe his job. I have been running OBDLink MX for years and some time you can get a communication error, but this is nothing to worry about. Clear the U code and you are done.

If you want a better option get torque Pro. I'm working with someone to get better PID for the mini. Let see what we come up with.