The automobile dictionary meaning of the engine code is available online but you must look for the right meaning of the car engine code what is found from the car manufacturer. The real meaning of the engine P1545 Code is available and you will find the automobile dictionary meaning of the car engine code. The automobile dictionary meaning of the engine code is p for Powertrain Code Problem is related engine, transmission and emissions systems. 1 is MFG – Manufacturer Specific. 5 is Computer And Auxiliary Outputs. 4 is BBV Sensor Circuit Low Voltage and 5 for Park or Neutral Position (PNP) Switch Circuit Engine Torque Signal Circuit.