The B1641 Code is functional for the car engine and during the car diagnosed, the engine code comes. You need to know the dictionary meaning to get idea of the problem. You also need to use some more information like name of the manufacturer and model number as well. The dictionary meaning of the code is also important thing and the dictionary meaning of the code is B means Body Code Problem is antilock brake system, electronic suspension and steering systems. 1 means MFG – Manufacturer Specific. 6 means Vehicle Speed Control and Idle Control System. 4 means BBV Sensor Circuit Low Voltage and 1 means TFP Valve Position Switch-Drive Without Drive Ratio.