Daewoo Lanos 2001 90000 miles
When I bought my vehicle, the check was turned on, but I was told nothing happened. After three days, it turned off and I did not pay much attention to it. However, after three months, it has now appeared again, and I still do not know what it means. Can anyone please tell me what I should do? Another thing I would like to mention is that, when stopping the engine, it sometimes whistles, indicating that I have not turned off the lights, but others it doesn't. What might be failing? Thank you very much for your help.