The engine code is a language of the car engine. If you know the meaning of the code, you can identify the problem of the car engine. The real meaning of the engine P2840 Code should be taken from the right source and the right source is automobile manufacturer. The automobile dictionary meaning is also important and do not take this meaning if you do not know the real meaning. The real meaning is important thing first and later you can use the general meaning of the code is necessary. The general meaning of the code found online and it is very useful for learning.