WenmarOpen by Wenmar Pro

Service bulletins for the 2015 Chrysler 300

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.

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

About P121B on the 2015 Chrysler 300: what the code means, and the bulletins and recalls about the same components.

By type

By component

By trouble code

Only bulletins with trouble code: P121B are shown. Show all

Bulletins, newest first
18-035-15 REVA2018-12-10. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM; ENGINE. Flash: 6.2L / 6.4L Diagnostic And System Improvements This bulletin involves reprogramming of the Powertrain Control Module (PCM) with the latest software. A small number of customers may experience one or more of the following symptoms and/or a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs). Symptoms: ? Unable to accurately increase or decrease the cruise control set speed using the resume or set buttons while the instrument cluster is set on metric units. Instead of changing vehicle speed by 1 KPH when pressing the buttons, the vehicle speed will increase approximately 1.6 KPH. ? Slight spark knock condition during aggressive high speed driving which may prevent the vehicle from achieving maximum top speed. DTCs: ? P1217 - Active Exhaust Valve 1 Performance ? P121B - Active Exhaust Valve 2 Performance ? P2227 - Barometric Pressure Circuit Performance
18-045-162018-06-11. Service bulletin. POWER TRAIN. Flash: 6.4L Diagnostic And System Improvements This bulletin involves reprogramming of the Powertrain Control Module (PCM) with the latest available software. A small number of customers may experience one or more of the following symptoms and/or a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs): · P1217 - Active Exhaust Valve 1 Performance. · P121B - Active Exhaust Valve 2 Performance. In addition, customers may also comment on the following: · Unable to accurately increase or decrease the cruise control set speed using the resume or set buttons while the instrument cluster is set on metric units. Instead of changing vehicle speed by 1 KPH when pressing the buttons, the vehicle speed will increase approximately 1.6 KPH. · Slight spark knock condition during aggressive high speed driving which may prevent the vehicle from achieving maximum top speed.
18-045-16 REV. A2016-11-07. Service bulletin. POWER TRAIN. "FLASH: DIAGNOSTIC AND SYSTEM IMPROVEMENTS THIS BULLETIN INVOLVES REPROGRAMMING OF THE POWERTRAIN CONTROL MODULE (PCM) WITH THE LATEST AVAILABLE SOFTWARE. CUSTOMERS MAY EXPERIENCE ONE OR MORE OF THE FOLLOWING SYMPTOMS AND/OR A MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATION. UPON FURTHER INVESTIGATION THE TECHNICIAN MAY FIND ONE OR MORE OF THE FOLLOWING DTCS: · **P2299 - BRAKE PEDAL POSITION/ACCELERATOR PEDAL POSITION INCOMPATIBLE. · P0456 - EVAP SYSTEM SMALL LEAK. · P2610 - PCM INTERNAL ENGINE OFF TIMER PERFORMANCE. · P2172 - HIGH AIRFLOW/VACUUM LEAK DETECTED (INSTANTANEOUS ACCUMULATION). · P0123 - THROTTLE POSITION SENSOR 1 CIRCUIT HIGH. · P0223 - THROTTLE POSITION SENSOR 2 CIRCUIT HIGH. · P0122 - THROTTLE POSITION SENSOR 1 CIRCUIT LOW. · P0222 - THROTTLE POSITION SENSOR 2 CIRCUIT LOW. · P0335 - CRANKSHAFT POSITION SENSOR CIRCUIT. · P0339 - CRANKSHAFT POSITION SENSOR INTERMITTENT.** · P1217 - ACTIVE EXHAUST VALVE 1 PERFORMANCE. · P121B - ACTIVE EXHAUST VALVE 2 PERFORMANCE. **THE FOLLOWING SOFTWARE ENHANCEMENT IS ALSO AVAILABLE: · CHANGE TO PURGE VAPOR CONTROL CALIBRATION.** IN ADDITION, CUSTOMERS MAY ALSO COMMENT ON THE FOLLOWING: · UNABLE TO ACCURATELY INCREASE OR DECREASE THE CRUISE CONTROL SET SPEED USING THE RESUME OR SET BUTTONS WHILE THE INSTRUMENT CLUSTER IS SET ON METRIC UNITS. INSTEAD OF CHANGING VEHICLE SPEED BY 1 KPH WHEN PRESSING THE BUTTONS, THE VEHICLE SPEED WILL INCREASE APPROXIMATELY 1.6 KPH. · SLIGHT SPARK KNOCK CONDITION DURING AGGRESSIVE HIGH SPEED DRIVING WHICH MAY PREVENT THE VEHICLE FROM ACHIEVING MAXIMUM TOP SPEED."
18-045-162016-07-07. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). This bulletin involves reprogramming of the Powertrain Control Module (PCM) with the latest available software. SYMPTOM/CONDITION: A small number of customers may experience one or more of the following symptoms and/or a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs): • P1217 - Active Exhaust Valve 1 Performance. • P121B - Active Exhaust Valve 2 Performance. In addition, customers may also comment on the following: • Unable to accurately increase or decrease the cruise control set speed using the resume or set buttons while the instrument cluster is set on metric units. Instead of changing vehicle speed by 1 KPH when pressing the buttons, the vehicle speed will increase approximately 1.6 KPH. • Slight spark knock condition during aggressive high speed driving which may prevent the vehicle from achieving maximum top speed.

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