The right meaning of the car engine P1506 Code lets us know about the problem of the car engine. From the meaning of the code, it is also known the location of the car engine problem. For the problem of the powertrain, the car engine has got problem in the car engine. You can know rest of the meaning of the car engine code from automobile dictionary meaning and it is p for Powertrain Code Problem is related engine, transmission and emissions systems. 1 for MFG – Manufacturer Specific. 5 for Computer And Auxiliary Outputs. 0 for IC Circuit High Voltage and 6 for Cruise Control System – Vehicle Accel Too High.