Borrow or purchase a OBDii Code scanner to pull the trouble code. That is what the light is telling you. It can be any number of thing. An auto part store can do it for free as well. Post the codes back here on this thread to get some additional help.
The orange light is less drastic than the red, or flashing red. The orange light can signify something as simple as a loose gas cap, which is the first thing to check. If the car is running with no sign of a problem, and if the light continues after a few restarts after you tighten the gas cap, you can schedule a service trip at your convenience: it's not urgent. If the light changes to red, it can indicate a misfire or overheating system and requires greater attention. Have the car serviced soon. If the light flashes, this is urgent and you stop the car.
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