Technical Service Bulletin 18-020-26 — 2021 RAM 1500

Flash: Powertrain Control Module (PCM) Updates **Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300-00 - Multiple Cylinder Misfire - in Active or Stored status set during cold start catalyst heating. ● P0301-00 - Cylinder 1 Misfire - in Active or Stored status set during cold start catalyst heating. ● P0302-00 - Cylinder 2 Misfire - in Active or Stored status set during cold start catalyst heating. ● P0303-00 - Cylinder 3 Misfire - in Active or Stored status set during cold start catalyst heating. ● P0304-00 - Cylinder 4 Misfire - in Active or Stored status set during cold start catalyst heating. ● P0305-00 - Cylinder 5 Misfire - in Active or Stored status set during cold start catalyst heating. ● P0306-00 - Cylinder 6 Misfire - in Active or Stored status set during cold start catalyst heating.** ● P0335 - Crankshaft Position Sensor Circuit. ● P0339 - Crankshaft Position Sensor Intermittent. **Customers may comment on one or more of the following: ● Vehicle has a rough idle. ● Engine has a miss. ● Noisy valvetrain.** Other software enhancement included with this update: ● Idle stability improvements during Electronic Stability Control (ESC) events. , Claims Data and Special Tools sections, updated LOP number, Repair Procedure and new Repair Procedure notes. **REPAIR SUMMARY: