I Had Took my car to auto zone for a test because my engine light is on and it had 0 codes. Why is that?
Could be the service light and not the check engine light, in that case your owners manual will tell you how to reset it. Also those are not comprehensive code readers at Auto Zone and you could have a body or traction control module that is detecting a problem and turning on the check engine light, these are manufacturer specific codes and generic code readers like theirs do not scan or recognize those codes, and will show no codes! All those simple readers are meant to show are OBDII codes which all cars after 96 are mandated to show and are to be uniform.
Maybe its just a maintenance light, not check engine light. If it is check engine Autozone probably doesn't use the best reader in the world. Dealer or reputable repair shop might have better luck.
They must be using a cheap reader. The cheap readers can't read all the systems. I have 2 different readers you can plug the one in to the car and it will say no codes unplug it and plug the other reader in and it will say 6 codes because it can access all systems.
