Picked this unit up to add to tool box, for later use. But last weekend my mothers GMC Acadia through out an error code while hauling a trailer. Plugged it in and it read the error. Knowing the car probably through do to the stress from hauling the trailer. I used the unit to reset the code, it took no longer than 4 Minutes to do the entire process. No error codes so far. Great add to my tool box.