if reading the generic fault codes from your vehicles obd II system is enough to be considered diagnostics then yes, but in my experience simply having this knowledge can easily mislead many people towards attempting to fix the "check engine" light just to learn that its not the light that needs to be fixed and the problem is more complicated than simply turning the light off (they aren't supposed to erase the codes, even after you buy a part from them and duct tape it into place. this may frustrate you but it is the correct course of action, just in case at a later time someone, even yourself possibly, need to review the stored Freeze Frame data stored in association with the fault in order to properly "git 'r done" . anyways, most vehicles have a system which turns the chk engine lamp off after several drive cycles where it doesn't detect the fault any longer)
Yes! They offer free battery, alternator, start testing. Also check engine codes with what and why they are on. You will still need to take your car to mechanic for a more detailed diagnostic.
Yes but they're not allowed to clear the codes. You can buy a code reader there and clear most codes yourself.
Thanks! Your answer is awaiting moderation.