The error U1099 Code is found in the car engine and it is necessary to know the right meaning of the code for fixing the meaning. You find various meanings of the same code but you will look only the right meaning what is provided by the car manufacturer. The automobile meaning of the code is not right thing for fixing the car. Once you follow the correct meaning of the code, you can easily solve the car engine problem. However, you need to use expertise and marchioness for solving the car engine problem. Do not drive the car with engine problem.