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Service bulletins for the 2025 Ram 1500

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

589 on file from NHTSA, as of 2026-10-19.

About P0306 on the 2025 Ram 1500: what the code means, and the bulletins and recalls about the same components.

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Only bulletins with trouble code: P0306 are shown. Show all

Bulletins, newest first
18-079-262026-10-16. Service bulletin. ENGINE. 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. ENGINE. 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.
18-072-262026-07-29. Service bulletin. ENGINE. 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.
18-031-25 REV. C2025-10-29. Service bulletin. POWER TRAIN. 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. ELECTRICAL SYSTEM. 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. ELECTRICAL SYSTEM. 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.**
18-031-252025-06-18. Service bulletin. POWER TRAIN. "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 - Knock/Combustion Vibration Sensor 1 Circuit. ● P0330 - Knock/Combustion Vibration Sensor 2 Circuit. ● P032A - Knock-Combustion Vibration Sensor C Circuit. ● P018B - Fuel Pressure Sensor ""B"" Circuit Range/performance. ● P2AF6 - Starter Relay 3 Stuck Off. ● P1CEA - Boost Side EVAP Purge System Performance. ● U0104 - 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. NOTE: If the software update is not completed, customers may have issues with registering vehicle in states with inspections due to the MIL being on (Only an issue if U0104/U0405 have set in life of vehicle). 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 cluster informing the driver to shift to park to restart the engine.** Other software improvements: ● Improvements related to fault codes P0300, P0301, P0302, P0303, P0304, P0305 and P0306 for cold start catalyst heating misfire.. This bulletin involves reprogramming the PCM and Ignition System Control Module (ISCM) and the with the latest available software"
09-011-252025-05-20. Service bulletin. ENGINE. "Misfire Diagnostic Trouble Codes (DTCs), Rough Idle, Valvetrain Noise Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0301 - Cylinder 1 Misfire. ● P0302 - Cylinder 2 Misfire. ● P0303 - Cylinder 3 Misfire. ● P0304 - Cylinder 4 Misfire. ● P0305 - Cylinder 5 Misfire. ● P0306 - Cylinder 6 Misfire. Customers may comment on one or more of the following: ● Rough idle. ● Valvetrain noise. "
08-087-252025-04-02. Service bulletin. ELECTRICAL SYSTEM. "Flash: Ignition System Control Module (ISCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle mustexhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0305-00 - Cylinder 5 Misfire. ● P0306-00 - Cylinder 6 Misfire. ● P0420-00 - Catalyst System Efficiency Below Threshold Bank 1. ● P0430-00 - Catalyst System Efficiency Below Threshold Bank 2. Customers may also comment on the following: ● Engine misfires. ● Damage to catalyst. This bulletin involves inspecting and possibly reprogramming the ISCM and the Powertrain Control Module (PCM) with the latest available software."
08-055-25 REV. A2025-03-11. Service bulletin. ELECTRICAL SYSTEM. "Flash: Ignition System Control Module (ISCM) 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): ● P2C30-00 - Ignition Coil Primary Circuit Fuse A. ● P2C31-00 - Ignition Coil Primary Circuit Fuse B. ● P0300-00 - Multiple Cylinder Misfire. ● P0301-00 - Cylinder 1 Misfire Detected. ● P0302-00 - Cylinder 2 Misfire Detected. ● P0303-00 - Cylinder 3 Misfire Detected. ● P0304-00 - Cylinder 4 Misfire Detected. ● P0305-00 - Cylinder 5 Misfire Detected. ● P0306-00 - Cylinder 6 Misfire Detected. ● P0420-00 - Catalyst System Efficiency Below Threshold Bank 1. ● P0430-00 - Catalyst System Efficiency Below Threshold Bank 2. Customers may also comment on the following: ● Engine hesitates/misfires *This bulletin involves reprogramming the ISCM with the latest available software.**"
08-031-25 REV. B2025-03-04. Service bulletin. ENGINE. "Flash: Ignition System Control Module (ISCM) 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): ● **P0300-00 - Multiple Cylinder Misfire. ● P0301-00 - Cylinder 1 Misfire Detected. ● P0302-00 - Cylinder 2 Misfire Detected. ● P0303-00 - Cylinder 3 Misfire Detected. ● P0304-00 - Cylinder 4 Misfire Detected. ● P0305-00 - Cylinder 5 Misfire Detected. ● P0306-00 - Cylinder 6 Misfire Detected. ● P0420-00 - Catalyst System Efficiency Below Threshold Bank 1. ● P0430-00 - Catalyst System Efficiency Below Threshold Bank 2.** ● P2C30-00 - Ignition Coil Primary Circuit Fuse A. ● P2C31-00 - Ignition Coil Primary Circuit Fuse B. Customers may also comment on the following: ● Engine hesitates/misfires This bulletin involves inspecting and possibly reprogramming the ISCM and the Powertrain Control Module (PCM) with the latest available software."
08-055-252025-03-04. Service bulletin. ELECTRICAL SYSTEM; ENGINE. "Flash: Ignition System Control Module (ISCM) 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): ● P2C30-00 - Ignition Coil Primary Circuit Fuse A. ● P2C31-00 - Ignition Coil Primary Circuit Fuse B. ● P0300-00 - Multiple Cylinder Misfire. ● P0301-00 - Cylinder 1 Misfire Detected. ● P0302-00 - Cylinder 2 Misfire Detected. ● P0303-00 - Cylinder 3 Misfire Detected. ● P0304-00 - Cylinder 4 Misfire Detected. ● P0305-00 - Cylinder 5 Misfire Detected. ● P0306-00 - Cylinder 6 Misfire Detected. ● P0420-00 - Catalyst System Efficiency Below Threshold Bank 1. ● P0430-00 - Catalyst System Efficiency Below Threshold Bank 2. Customers may also comment on the following: ● Engine hesitates/misfires. This bulletin involves inspecting and possibly reprogramming the ISCM with the latest available software "
18-071-24 REV. B2024-11-07. Service bulletin. POWER TRAIN. "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): ● **P0325 - Knock/Combustion Vibration Sensor 1 Circuit. ● P0330 - Knock/Combustion Vibration Sensor 2 Circuit. ● P032A - Knock-Combustion Vibration Sensor C Circuit.** ● P018B - Fuel Pressure Sensor ""B"" Circuit Range/performance. ● P2AF6 - Starter Relay 3 Stuck Off. ● P1CEA - Boost Side EVAP Purge System Performance. ● U0104 - 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. NOTE: If the software update is not completed, customers may have issues with registering vehicle in states with inspections due to the MIL being on (Only an issue if U0104/U0405 have set in life of vehicle). Other software improvements: ● Improvements related to fault codes P0300, P0301, P0302, P0303, P0304, P0305 and P0306 for cold start catalyst heating misfire. This bulletin involves reprogramming the PCM and Ignition System Control Module (ISCM) and the with the latest available software"
18-071-24 REV. A2024-10-14. Service bulletin. ENGINE; POWER TRAIN. "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): ● P018B - Fuel Pressure Sensor ""B"" Circuit Range/performance. ● P2AF6 - Starter Relay 3 Stuck Off. ● P1CEA - Boost Side EVAP Purge System Performance. ● U0104 - 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. NOTE: If the software update is not completed, customers may have issues with registering vehicle in states with inspections due to the MIL being on (Only an issue if U0104/U0405 have set in life of vehicle). Other software improvements: ● Improvements related to fault codes P0300, P0301, P0302, P0303, P0304, P0305 and P0306 for cold start catalyst heating misfire. This bulletin involves reprogramming the PCM and Ignition System Control Module (ISCM) and the with the latest available software."
18-071-242024-09-25. Service bulletin. POWER TRAIN. "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): ● P018B - Fuel Pressure Sensor ""B"" Circuit Range/performance. ● P2AF6 - Starter Relay 3 Stuck Off. ● P1CEA - Boost Side EVAP Purge System Performance. ● U0104 - 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. NOTE: If the software update is not completed, customers may have issues with registering vehicle in states with inspections due to the MIL being on (Only an issue if U0104/U0405 have set in life of vehicle). Other software improvements: ● Improvements related to fault codes P0300, P0301, P0302, P0303, P0304, P0305 and P0306 for cold start catalyst heating misfire. This bulletin involves reprogramming the PCM and Ignition System Control Module (ISCM) and the with the latest available software."

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.