The dictionary meaning of the B2156 Code is B for Body Code Problem is antilock brake system, electronic suspension and steering systems. 2 for MFG – Manufacturer Specific. 1 for Transmission. 5 for TP Sensor Learn Not Complete and 6 for Cruise Control System – Vehicle Accel Too High. So, it is identified that the body of the engine has the problem. You have nothing to do with car if you have no idea how to solve the engine of the car. The dictionary meaning of the code is general meaning but real meaning of the code is necessary to solve it.