BMW Repair: Bmw 525i wagon, coolant level, bmw 525i

Question
i have a bmw 525i wagon it keep saying something about the coolant level and the check engine light just recently came on. i just recently bought this car but my boyfriend check the coolant level and said it was fine. Why would the check engine light come on? the car also started smoking a little more than before. it drives fine. do it have a plug part/thing to diagnose the car?

Answer
The coolant level light may be the sensor,if the level is in fact fine.The check engine light maybe related but it should be scanned to see if it is related.What year  is it,if it is 96 or newer than you will need to have a scanner to remove and properly diagnose the lamp problem.