The code B1223 is used for error engine and by the code, it is easy to identify the problem but that is why, you need to take help from manual of the car. The code B1223 Fuel Temperature Sensor #1 Circuit Open so you have to verify ODB-II Engine Error Code list. It is also essential to know the model and manufacturer of the car. The B1223 Code describes many things. The main thing is to verify the process of the VCT solenoid. The dictionary meaning of the B1223 code is B for body code, 1 for MFG, 2 for Computer and Auxiliary Outputs, 2 for Cruise Control Servo Indicates Low and 3 for TFP Valve Position Switch-Drive Without Drive Ratio.