P04FC: Chrysler 300 crankcase-ventilation performance software case

A performance code with a calibration path

FCA documented P04FC, crankcase-ventilation-system performance, on a defined group of 2020 Chrysler 300 vehicles. The listed correction is a PCM software update. This establishes that calibration is part of the diagnostic possibilities for that application; it does not show that every crankcase hose, valve or engine with P04FC is mechanically sound.

Keep the other complaints separate

The same release includes cruise-control speed limitation and brake-pedal behavior at higher altitude. These are additional concerns addressed by the package. They should not be presented as inevitable symptoms of the crankcase-ventilation fault or used to claim a single failed component explains all three. Record the actual complaint and full code set instead.

What makes the software case applicable

The model year, LX platform, ERB engine and build cutoff need to match. FCA requires related systems to be checked and other conditions to be repaired before applying the bulletin. A workshop should verify the installed calibration, apply the appropriate current update when indicated and reassess the original fault and drivability behavior. If P04FC remains active afterward, return to the vehicle-specific crankcase-ventilation diagnosis rather than repeatedly clearing it. The bulletin supplies no universal crankcase-pressure threshold or part-replacement instruction. A hard-brake-pedal complaint also requires its own appropriate assessment; the existence of a historical software release does not establish that a vehicle is safe to drive.

Source and applicability

FCA 18-083-20 covers 2020 Chrysler 300 LX with the 3.6 L ERB engine, built on or before July 28, 2020 in the listed markets.

Manufacturer bulletin, page 1 · Manufacturer bulletin, page 2