The dictionary meaning of the B2318 Code is available online and it is not very important thing for solving the problem of the car engine. The common meaning of the code is B is Body Code Problem is antilock brake system, electronic suspension and steering systems. 2 is MFG – Manufacturer Specific. 3 is IC Module 4X Ref Circuit Intermittent, No Pulses. 1 is Low Coolant Circuit and 8 for PCM Stack Overrun. However, you should get the real meaning of the code and that is why, you need to read the manual of the car engine. Do not think to fix the engine according to the dictionary meaning.