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Service bulletins for the 2020 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.

1228 on file from NHTSA, as of 2026-10-19.

About P0305 on the 2020 Ram 1500: what the code means, and the bulletins and recalls about the same components.

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Only bulletins with trouble code: P0305 are shown. Show all

Bulletins, newest first
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. "
18-002-232023-02-13. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING; EXTERIOR LIGHTING; ELECTRICAL SYSTEM; BACK OVER PREVENTION; FUEL SYSTEM, GASOLINE; SERVICE BRAKES, HYDRAULIC; PARKING BRAKE. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have been set: **P2183 - Engine Coolant Temperature Sensor 2 Circuit Performance. P016F - Closed Loop Fuel Pressure Control At Limit - Pressure Too Low. P025C - Fuel Pump Module Control Circuit Low. P208B - Reductant Pump 1 Control Performance. P0403-00 - EGR Control Circuit Open ? Disabled Fault.** P225D-00 - NOX Sensor 1/1 Performance Signal Stuck Low. P249C-00 - Excessive Time To Enter Closed Loop Reductant Injection Control. P065A - Generator System Performance. P00F4-00 - Humidity Sensor Circuit Low. P20FB-00 - Reductant Pump 2 Control Performance. P200A-00 - Intake Manifold Runner Performance Bank 1. P200B-00 - Intake Manifold Runner Performance Bank 2. P2610 - PCM Internal Engine Off Timer Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1/2 Correlation. P22FA-00 - NOX Sensor Performance Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality (additional software enhancement). P0300-00 - Multiple Cylinder Misfire (cold ambient temperature). P0301-00 - Cylinder 1 Misfire (cold ambient temperature). P0302-00 - Cylinder 2 Misfire (cold ambient temperature). P0303-00 - Cylinder 3 Misfire (cold ambient temperature). P0304-00 - Cylinder 4 Misfire (cold ambient temperature). P0305-00 - Cylinder 5 Misfire (cold amb
18008212023-01-17. Service bulletin. ELECTRICAL SYSTEM; BACK OVER PREVENTION; FUEL SYSTEM, GASOLINE; EXTERIOR LIGHTING; SERVICE BRAKES, HYDRAULIC; FUEL SYSTEM, DIESEL. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following DTCs have been set: P225D-00 - Nox Sensor 1/1 Performance - Signal Stuck Low. P249C-00 - Excessive Time to Enter Closed Loop Reductant Injection Control. P065A - Generator System Performance. P00F4-00 - Humidity Sensor Circuit Low. Improved VGT cleaning to reduce false failures for P00AF field issue. P0106-00 - Manifold Absolute Pressure Sensor Performance. P20FB-00 - Reductant Pump 2 Control Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2610 - PCM Internal Engine Off Timer Performance. Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High to Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality (additional software enhancement). P0300-00 - Multiple Cylinder Misfire (cold ambient temperature). P0301-00 - Cylinder 1 Misfire (cold ambient temperature). P0302-00 - Cylinder 2 Misfire (cold ambient temperature). P0303-00 - Cylinder 3 Misfire (cold ambient temperature). P0304-00 - Cylinder 4 Misfire (cold ambient temperature). P0305-00 - Cylinder 5 Misfire .
18008212022-10-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE; FUEL SYSTEM, DIESEL; ELECTRICAL SYSTEM; BACK OVER PREVENTION; SERVICE BRAKES, HYDRAULIC; EXTERIOR LIGHTING; FUEL SYSTEM, GASOLINE. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following DTCs have been set: P225D-00 - Nox Sensor 1/1 Performance - Signal Stuck Low. P249C-00 - Excessive Time To Enter Closed Loop Reductant Injection Control. P065A - Generator System Performance. P00F4-00 - Humidity Sensor Circuit Low. Improved VGT cleaning to reduce false failures for P00AF field issue. P0106-00 - Manifold Absolute Pressure Sensor Performance. P20FB-00 - Reductant Pump 2 Control Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2610 - PCM Internal Engine Off Timer Performance. Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature).
18008212022-10-17. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following DTCs have been set: P225D-00 - Nox Sensor 1/1 Performance - Signal Stuck Low. P249C-00 - Excessive Time To Enter Closed Loop Reductant Injection Control. P065A - Generator System Performance. P00F4-00 - Humidity Sensor Circuit Low. Improved VGT cleaning to reduce false failures for P00AF field issue. P0106-00 - Manifold Absolute Pressure Sensor Performance. P20FB-00 - Reductant Pump 2 Control Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2610 - PCM Internal Engine Off Timer Performance. Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature).
18022212022-09-26. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the one or more of the following DTCs have been set:P0300 - Multiple Cylinder Misfire. P0301 - Cylinder 1 Misfire. P0302 - Cylinder 2 Misfire. P0303 - Cylinder 3 Misfire. P0304 - Cylinder 4 Misfire. P0305 - Cylinder 5 Misfire. P0306 - Cylinder 6 Misfire. P0307 - Cylinder 7 Misfire. P0308 - Cylinder 8 Misfire. The customer may also experience one or more of the following:Rough idle/misfire only after cold start Auto Park system is unable to be manually over-ridden after an Auto Park event. Auto Park disabled message will not display in cluster. ECO light does not illuminate in the cluster when Multiple Displacement System (MDS) is active(EMEA, LATAM and APAC). 2-3 kph (1.3-1.9 mph) difference between cruise set speed and the actual vehicle speed(EMEA, LATAM and APAC). Bump sensation during a coast down with light acceleration. Abnormal vibration when accelerating lightly during stop and go driving conditions.
18008212022-09-26. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM; BACK OVER PREVENTION; EXTERIOR LIGHTING; FUEL SYSTEM, GASOLINE; FUEL SYSTEM, DIESEL. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the followingDiagnostic Trouble Codes (DTCs) have been set:Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature). P0306-00 - Cylinder 6 Misfire (cold ambient temperature). P01CB-00 - Cylinder 1 Injection Timing Performance - Over Retarded. P01CC-00 - Cylinder 1 Injection Timing Performance - Over Advanced. P01CD-00 - Cylinder 2 Injection Timing Performance - Over Retarded. P01CE-00 - Cylinder 2 Injection Timing Performance - Over Advanced. P01CF-00 - Cylinder 3 Injection Timing Performance - Over Retarded.
18-008-21 REV. A2021-06-28. Service bulletin. ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following DTCs have been set: P225D-00 - Nox Sensor 1/1 Performance - Signal Stuck Low. P249C-00 - Excessive Time To Enter Closed Loop Reductant Injection Control. P065A - Generator System Performance. P00F4-00 - Humidity Sensor Circuit Low. Improved VGT cleaning to reduce false failures for P00AF field issue. P0106-00 - Manifold Absolute Pressure Sensor Performance. P20FB-00 - Reductant Pump 2 Control Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2610 - PCM Internal Engine Off Timer Performance. Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature).
18-022-212021-03-15. Service bulletin. POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the one or more of the following DTCs have been set:P0300 - Multiple Cylinder Misfire. P0301 - Cylinder 1 Misfire. P0302 - Cylinder 2 Misfire. P0303 - Cylinder 3 Misfire. P0304 - Cylinder 4 Misfire. P0305 - Cylinder 5 Misfire. P0306 - Cylinder 6 Misfire. P0307 - Cylinder 7 Misfire. P0308 - Cylinder 8 Misfire. The customer may also experience one or more of the following:Rough idle/misfire only after cold start Auto Park system is unable to be manually over-ridden after an Auto Park event. Auto Park disabled message will not display in cluster. ECO light does not illuminate in the cluster when Multiple Displacement System (MDS) is active(EMEA, LATAM and APAC). 2-3 kph (1.3-1.9 mph) difference between cruise set speed and the actual vehicle speed(EMEA, LATAM and APAC). Bump sensation during a coast down with light acceleration. Abnormal vibration when accelerating lightly during stop and go driving conditions.
18-008-212021-03-15. Service bulletin. POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the followingDiagnostic Trouble Codes (DTCs) have been set:Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature). P0306-00 - Cylinder 6 Misfire (cold ambient temperature). P01CB-00 - Cylinder 1 Injection Timing Performance - Over Retarded. P01CC-00 - Cylinder 1 Injection Timing Performance - Over Advanced. P01CD-00 - Cylinder 2 Injection Timing Performance - Over Retarded. P01CE-00 - Cylinder 2 Injection Timing Performance - Over Advanced. P01CF-00 - Cylinder 3 Injection Timing Performance - Over Retarded.
18-062-20 REV. A2021-03-01. Service bulletin. ENGINE; ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the one or more of the following DTCs have been set:P0300 - Multiple Cylinder Misfire. P0301 - Cylinder 1 Misfire. P0302 - Cylinder 2 Misfire. P0303 - Cylinder 3 Misfire. P0304 - Cylinder 4 Misfire. P0305 - Cylinder 5 Misfire. P0306 - Cylinder 6 Misfire. P0307 - Cylinder 7 Misfire. P0308 - Cylinder 8 Misfire. The customer may experience one or more of the following:Rough idle/misfire only after cold start ECO light does not illuminate in the cluster when Multiple Displacement System (MDS) is active(EMEA, LATAM and APAC). 2-3 kph (1.3-1.9 mph) difference between cruise set speed and the actual vehicle speed(EMEA, LATAM and APAC).
18-008-20 REV. A2021-03-01. Service bulletin. FUEL SYSTEM, GASOLINE; EQUIPMENT; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. DTCs have been set:Change DTC number from P0101-00 to P0109-00 - Mass Air Flow Sensor Performance. P015E - Excessive Time to Enter Closed Loop Fuel Timing Control. P0534-00 - AC Refrigerant System A Charge Loss. P26FB-00 - EGR Cooler Bypass Control Stuck Closed Bank 1. P04DB-00 - Crankcase Ventilation System Disconnected. P204F-00 - Reductant System Performance. P200A-00 - Intake Manifold Runner Performance - Bank 1. P200B-00 - Intake Manifold Runner Performance - Bank 2. P2D2D-00 - Cold Start Intake Manifold Runner Performance Bank 1. P2D2E-00 - Cold Start Intake Manifold Runner Performance Bank 2. P2199-00 - Intake Air Temperature Sensor 1 / 2 Correlation. P22FA-00 - NOX Sensor Performance - Slow Response High To Low Bank 1 Sensor 1. P2002-00 - Diesel Particulate Filter Efficiency Below Threshold. P0087-00 - Fuel Rail Pressure Too Low. P0128-00 - Thermostat Rationality(additional software enhancement). P0300-00 - Multiple Cylinder Misfire(cold ambient temperature). P0301-00 - Cylinder 1 Misfire(cold ambient temperature). P0302-00 - Cylinder 2 Misfire(cold ambient temperature). P0303-00 - Cylinder 3 Misfire(cold ambient temperature). P0304-00 - Cylinder 4 Misfire(cold ambient temperature). P0305-00 - Cylinder 5 Misfire(cold ambient temperature). P0306-00 - Cylinder 6 Misfire (cold ambient temperature). P01CB-00 - Cylinder 1 Injection Timing Performance - Over Retarded. P01CC-00 - Cylinder 1 Injection Timing Performance - Over Advanced. P01CD-00 - Cylinder 2 Injection Timing Performance - Over Retarded. P01CE-00 - Cylinder 2 Injection Timing Performance - Over Advanced. P01CF-00 - Cylinder 3 Injection Timing Performance - Over Retarded. P01D0-00 - Cylinder 3 Injection Timing Performance - Over Advan

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