WenmarOpen by Wenmar Pro

P0300 on the 2025 Ram 1500

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

Bulletins for this model year that name P0300
18-079-262026-10-16. Service bulletin. Flash: Powertrain Control Module (PCM) Update Customers may experience a Malfunction Indicator Lamp (MIL) illumination, and the vehicle may exhibit SYMPTOM: or 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. Customers may also comment on one or more of the following: ● Vehicle has a rough idle. ● Engine has a miss. ● Noisy valvetrain. This bulletin involves inspecting the PCM software level and, if necessary, reprogramming the PCM with the latest available software.
18-079-262026-10-16. Service bulletin. Flash: Powertrain Control Module (PCM) Update Customers may experience a Malfunction Indicator Lamp (MIL) illumination, and the vehicle may exhibit SYMPTOM: or 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. Customers may also comment on one or more of the following: ● Vehicle has a rough idle. ● Engine has a miss. ● Noisy valvetrain. This bulletin involves inspecting the PCM software level and, if necessary, reprogramming the PCM with the latest available software.
18-077-262026-08-26. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set the following Diagnostic Trouble Code (DTC): ● P0300 - Multiple Cylinder Misfire. Customers may experience one of the following: ● Vehicle runs rough on initial cold start only after an overnight or extended soak. **This bulletin involves reprogramming the PCM with the latest available software.**
18-072-262026-07-29. Service bulletin. GMET6 SO MIL Changes At Elevation Above 1,000 FT Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300-00 - Multiple Cylinder Misfire. ● P0301-00 - Cylinder 1 Misfire. ● P0302-00 - Cylinder 2 Misfire. ● P0303-00 - Cylinder 3 Misfire. ● P0304-00 - Cylinder 4 Misfire. ● P0305-00 - Cylinder 5 Misfire. ● P0306-00 - Cylinder 6 Misfire. Customers may experience the following: ● Engine missing or running rough.
18-071-262026-07-29. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **U0104-00 - Lost Communication With Cruise Control Module (NA Market Only) (In Active or Stored status). ● U0405-00 - Invalid Data Received From Cruise Control Module (NA Market Only) (In Active or Stored status). NOTE: Vehicles setting DTCs U0405-00 and U0104-00 may experience an inability to be cleared.** ● P06DD-00 - Engine Oil Pressure Control Circuit Performance/Stuck Off. ● P0073-00 - Ambient Air Temperature Sensor Circuit "A" High. ● P0071-00 - Ambient Air Temperature Sensor Performance. ● P2C90-00 - Crankcase Ventilation System - Hose "A" Disconnected. ● P1CEA-00 - Boost Side EVAP Purge System Performance. ● P05BD-00 - Stop-start Mode Switch Range/Performance. ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking. ● U0673-00 - Lost Communication With Ion Sense Module. ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking - in ACTIVE or STORED status. ● P0325-00 - Knock/Combustion Vibration Sensor 1 Circuit - in ACTIVE or STORED status. ● P0330-00 - Knock/Combustion Vibration Sensor 2 Circuit - in ACTIVE or STORED status. ● P032A-00 - Knock-Combustion Vibration Sensor C Circuit - in ACTIVE or STORED status. ● P018B-00 - Fuel Pressure Sensor "B" Circuit Range/Performance - in ACTIVE or STORED status. ● P2AF6-00 - Starter Relay 3 Stuck Off - in ACTIVE or STORED status. ● 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. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
18-044-262026-03-25. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P0111-00 - Intake Air Temperature Sensor 1 Circuit Range Performance Bank 1. (In Active or Stored status) ● P0071-00 - Ambient Air Temperature Sensor Performance. (In Active or Stored status) ● P0072-00 - Ambient Air Temperature Sensor Circuit "A" Low. (In Active or Stored status) ● P0073-00 - Ambient Air Temperature Sensor Circuit "A" High. (In Active or Stored status) ● P0011-00 - Bank 1 Camshaft 1 Position Timing Over Advanced Or. (In Active or Stored status) ● P25E4-00 - B Camshaft Position - Unable To Achieve Locked Position Bank 1. (In Active or Stored status) ● P05BD-00 - Stop-Start Mode Switch Range/Performance. (In Active or Stored status) ● P0116-00 - Engine Coolant Temperature Sensor 1 Performance. (In Active or Stored status) ● P062B-00 - Internal Control Module Fuel Injector Control Performance. (In Active or Stored status) ● P0604-00 - Internal Control Module Random Access Memory Ram Error. (In Active or Stored status) ● P060C-00 - Internal Control Module Main Processor Performance. (In Active or Stored status)** ● P018B-00 - Fuel Pressure Sensor "B" Circuit Range/performance. **(In Active or Stored status)** ● P1CEA-00 - Boost Side EVAP Purge System Performance. **(In Active or Stored status)** ● P06DD-00 - Engine Oil Pressure Control Circuit Performance/Stuck Off. **(In Active or Stored status)** ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking. **(In Active or Stored status)** ● P0300-00 - Multiple Cylinder Misfire. **(In Active or Stored status)** Customers may also experience one or more of the following: ● **Oil Level High Warning in the Instrument Panel Cluster (IPC).** ● Fully Autonomous Parking Assist (FAPA) is not deactivated when accelerator pedal is pressed. ● Vehicle is not heating up fast enough at freezi
18-031-25 REV. C2025-10-29. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P06DD-00 - Engine Oil Pressure Control Circuit Performance/Stuck Off. ● P0073-00 - Ambient Air Temperature Sensor Circuit "A" High. ● P0071-00 - Ambient Air Temperature Sensor Performance. ● P2C90-00 - Crankcase Ventilation System - Hose "A" Disconnected. ● P1CEA-00 - Boost Side EVAP Purge System Performance. ● P05BD-00 - Stop-start Mode Switch Range/Performance. ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking. ● U0673-00 - Lost Communication With Ion Sense Module.** ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking - in ACTIVE or STORED status. ● P0325-00 - Knock/Combustion Vibration Sensor 1 Circuit - in ACTIVE or STORED status. ● P0330-00 - Knock/Combustion Vibration Sensor 2 Circuit - in ACTIVE or STORED status. ● P032A-00 - Knock-Combustion Vibration Sensor C Circuit - in ACTIVE or STORED status. ● P018B-00 - Fuel Pressure Sensor "B" Circuit Range/Performance - in ACTIVE or STORED status. ● P2AF6-00 - Starter Relay 3 Stuck Off - in ACTIVE or STORED status. ● 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. NOTE: To confirm the cold start catalyst heating, use WiTech Freeze Frame data, and confirm "Time Since Engine Start" less than 30 seconds and "Engine Coolant Temperature °F" less than 50 °C (122 °F) when Misfire Code was set. See Step 3 for more details. ● U0104-00 - Lost Communication With Cruise Control Module - in ACTIVE or STORED status. This software update will allow this permanent fault code to naturally clear. ● U0405-00 - Invalid Data Received From Cruise Control Module - in ACTIVE or STORED status. This software update will allow this permanent fault code to naturally clear. Customers may also experience one or more of the following: ● **Rough running engine. ● "Excessive Oil - Service Vehicle" message display in the Instrument Panel Cluster (IPC). ● Vehicle is difficult to start. ● Potential stalling when coming to a stop with an immediate restart. NOTE: If the engine were to stall while stopping, a message would display in the IPC informing the driver to shift to Park to restart the engine.* This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
18-031-25 REV. B2025-10-02. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking - in ACTIVE or STORED status. ● P0325-00 - Knock/Combustion Vibration Sensor 1 Circuit - in ACTIVE or STORED status. ● P0330-00 - Knock/Combustion Vibration Sensor 2 Circuit - in ACTIVE or STORED status. ● P032A-00 - Knock-Combustion Vibration Sensor C Circuit - in ACTIVE or STORED status. ● P018B-00 - Fuel Pressure Sensor "B" Circuit Range/performance - in ACTIVE or STORED status. ● P2AF6-00 - Starter Relay 3 Stuck Off - in ACTIVE or STORED status. ● 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. NOTE: To confirm the cold start catalyst heating, use WiTech Freeze Frame data, and confirm "Time Since Engine Start" less than 30 seconds and "Engine Coolant Temperature °F" less than 122°F (50°C) when Misfire Code was set. See Step 3 for more details. ● U0104-00 - Lost Communication With Cruise Control Module - in ACTIVE or STORED status. This software flash will allow these permanent fault codes to naturally clear. ● U0405-00 - Invalid Data Received From Cruise Control Module - in ACTIVE or STORED status. This software flash will allow these permanent fault codes to naturally clear.** Customers may experience the following: ● A potential to stall when coming to a stop with an immediate restart. If the engine were to stall while stopping, a message would display in the Instrument Panel Cluster (IPC) informing the driver to shift to park to restart the engine This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
18-031-25 REV. A2025-09-10. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P00C6-00 - Fuel Rail Pressure Too Low - Engine Cranking. ● P0325-00 - Knock/Combustion Vibration Sensor 1 Circuit. ● P0330-00 - Knock/Combustion Vibration Sensor 2 Circuit. ● P032A-00 - Knock-Combustion Vibration Sensor C Circuit. ● P018B-00 - Fuel Pressure Sensor "B" Circuit Range/performance. ● P2AF6-00 - Starter Relay 3 Stuck Off. ● P1CEA-00 - Boost Side EVAP Purge System Performance. ● U0104-00 - Lost Communication With Cruise Control Module and U0405 - Invalid Data Received From Cruise Control Module may also be set. This software flash will allow these permanent fault codes to naturally clear. Customers may experience the following: ● A potential to stall when coming to a stop with an immediate restart. If the engine were to stall while stopping, a message would display in the Instrument Panel Cluster (IPC) informing the driver to shift to park to restart the engine. Other software improvements: ● **High pressure fuel pump actuation during cold start have been changed to shorten the cranking phase.** ● Improvements related to fault codes P0300, P0301, P0302, P0303, P0304, P0305 and P0306 for cold start catalyst heating misfire. **This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.**
09-025-252025-08-27. Service bulletin. Disconnected Purge Line Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300-00 - Multiple Cylinder Misfire. ● P0171-00 - System Too Lean Bank 1. ● P0174-00 - Fuel System 2/1 Lean. Customers may also experience one or more of the following: ● Vehicle running rough. ● Hissing noise from the engine. ● Vehicle does not start. This bulletin involves replacing the purge hose and canister purge tube.

19 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.