Good Bluetooth OBD2 Scanner

agesilaus wrote:
Be aware that standard readers will not read all the codes on most diesel trucks if you have one. That generally calls for a more expensive reader with a pack for your truck model unless something new has come out.

A basic reader just connects to the OBD-II port and implements the protocols for reading the data from the CAN bus and usually makes that data available vie USB or Bluetooth connection to a smart phone, laptop or other computing device. An app on the computing device does the work of decoding the codes, so just about any cheap reader will work if you're going to use it with a smart phone or computer, but you need to then find an APP that does the decoding you're interested in. All will handle the universal codes but if you want access to vehicle specific codes you need to find an APP that offers that option. Almost all the APPs available will work with any reader that provides the data via USB or Bluetooth. Many of the lower cost apps also don't include the ability to reset codes on the vehicle. More expensive OBD-II readers can operate without the need for a smart phone or laptop and incorporate decode logic for the codes they read, but generally come with the same limitation of being able to handle universal codes but may not be able to deal with vehicle specific codes without firmware upgrades.