The automobile meaning of the C1904 Code is not very helpful and it is necessary to find the real meaning. The real meaning of the code is associated with the car manufacturer. Do not allow wrong meaning of the code what may lead the car engine to more problem. Do not use any other meaning for fixing the car engine problem. There are several causes of the engine problem and it is important to identify the real meaning of the code. If the real meaning of the code is unknown, it is difficult to solve the car engine problem easily.