The dictionary meaning of the B1858 Code is B for Body Code Problem is antilock brake system, electronic suspension and steering systems. 1 for MFG – Manufacturer Specific. 8 for Ignition System or Misfire. 5 for TP Sensor Learn Not Complete and 8 for PCM Stack Overrun. The dictionary meaning lets you know that the body of the engine has the problem but for fixing the problem, you need to know the real meaning of the code and it can be known from the manufacturer name and model number. For fixing the problem of the engine, it is necessary to use expensive machines and tools.