I bought two ELM327 OBD2 Bluetooth interfaces, and keep one in each of my cars so can immediately read the stored codes whenever the engine warning light comes on. They work in conjunction with an app suitable for whatever mobile device you have (I use the 'Car Scanner' app on my Android phone). Bought my interfaces from here (free delivery)...
https://uk.gearbest.com/car-gadgets/...ml?wid=1433363
As said, OBD2 is a universal standard. However, for some odd reason, some readers do not work with some vehicles.