# P121B on the 2015 Dodge Challenger

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.

This code is specific to a manufacturer and is not described here.

## Bulletins for this model year that name P121B

- [10219908](https://open.wenmarpro.com/bulletins/10219908), 2022-09-15: Flash: Powertrain Diagnostic and System Enhancements This bulletin involves reprogramming the Powertrain Control Module \(PCM\) with the latest available software. Customers may experience a Malfunction Indicator Lamp \(MIL\) Illumination. Upon further investigation, the technician may find one or more of the following Diagnostic Trouble Codes \(DTCs\) stored in the PCM memory:P0456 \- EVAP System Small Leak. U1424 \- Implausible Engine Torque Signal Received. P0335 \- Crankshaft Position Sensor Circuit. P0339 \- Crankshaft Position Sensor Intermittent. P2299 \- Brake Pedal Position/Accelerator Pedal Position Incompatible. P2227 \- Barometric Pressure Circuit Performance. P1611 \- Supercharger Bypass Valve Position Sensor 1 Circuit High. P0513 \- Invalid Skim Key. P0300 \- Multiple Cylinder Misfire \(Sales Code DEC only\). P1613 \- Turbocharger/Supercharger Boost Pressure Sensor/Mass Air Flow Sensor Correlation. P1217 \- Active Exhaust Valve 1 Performance. P121B \- Active Exhaust Valve 2 Performance. The P0513 DTC is set during remote starting the vehicle and nearly simultaneously pressing the key fob button against the Keyless Ignition Node \(KIN\) causing an engine stall.The PCM software also enables freeze frame/failure records to be stored for the following diagnostic trouble codes:P0102 \- MAF sensor circuit shorted to ground. P0103 \- MAF Sensor Circuit shorted High. P0607 \- ECU Internal Performance. P060E \- Level 2 TPS Sensor Coherency Check Has Failed. P1610 \- Supercharger Bypass Valve Position Sensor 1 Circuit Low. P1611 \- Supercharger Bypass Valve Position Sensor 1 Circuit High. P1616 \- Supercharger Bypass Valve Position Sensor 2 Circuit Low. P1617 \- Supercharger Bypass Valve Position Sensor 2 Circuit High. P1620 \- Supercharger Bypass Valve Control Open Circuit. P1627 \- Supercharger Bypass Valve Position Sensor 1/2 Correlation. P162A \- Supercharger Bypass Valve Actuator Control System \- Max PWM Exceeded.
- [10150624](https://open.wenmarpro.com/bulletins/10150624), 2018-12-10: 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
- [10139966](https://open.wenmarpro.com/bulletins/10139966), 2018-06-11: Flash: 6.2L Powertrain Diagnostic And System Enhancements This bulletin involves selectively erasing and reprogramming the Powertrain Control Module \(PCM\) and Transmission Control Module \(TCM\) with new software. A small number of customers may experience a Malfunction Indicator Lamp \(MIL\) Illumination. Upon further investigation, the technician may find one or more of the following Diagnostic Trouble Codes \(DTCs\) stored in the PCM memory: \*\*P0456 \- EVAP System Small Leak. P1611 \- Supercharger Bypass Valve Position Sensor 1 Circuit High. P0513 \- Invalid Skim Key.\*\* P0300 \- Multiple Cylinder Misfire \(manual transmission applications only\). P1613 \- Turbocharger/Supercharger Boost Pressure Sensor/Mass Air Flow Sensor Correlation. P2227 \- Barometric Pressure Circuit Performance. P1217 \- Active Exhaust Valve 1 Performance. P121B \- Active Exhaust Valve 2 Performance. \*\*The P0513 code is set during remote starting the vehicle and nearly simultaneously pressing the Key Fob button against the Keyless Ignition Node \(KIN\) causing an engine stall.\*\* \*\*In addition the PCM software also enables freeze frame/failure records to be stored for the following Diagnostic Trouble Codes: P0102 \- MAF sensor circuit shorted to ground. P0103 \- MAF Sensor Circuit shorted High. P0607 \- ECU Internal Performance. P060E \- Level 2 TPS sensor coherency check has failed. P1610 \- Supercharger Bypass Valve Position Sensor 1 Circuit Low. P1611 \- Supercharger Bypass Valve Position Sensor 1 Circuit High. P1616 \- Supercharger Bypass Valve Position Sensor 2 Circuit Low. P1617 \- Supercharger Bypass Valve Position Sensor 2 Circuit High. P1620 \- Supercharger Bypass Valve Control Open Circuit. P1627 \- Supercharger Bypass Valve Position Sensor 1/2 Correlation. P162A \- Supercharger Bypass Valve Actuator Control System \- Max PWM Exceeded. P162C \- Supercharger Bypass Valve Control Circuit.\*\* In addition, customers may also comment on the following:
- [10139964](https://open.wenmarpro.com/bulletins/10139964), 2018-06-11: 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.
- [10084055](https://open.wenmarpro.com/bulletins/10084055), 2016-11-07: "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."
- [10076308](https://open.wenmarpro.com/bulletins/10076308), 2016-07-07: OVERVIEW: This bulletin involves selectively erasing and reprogramming the Powertrain Control Module \(PCM\) and Transmission Control Module \(TCM\) with new software. SYMPTOM/CONDITION: A small number of customers may experience a Malfunction Indicator Lamp \(MIL\) Illumination. Upon further investigation, the technician may find one or more of the following Diagnostic Trouble Codes \(DTCs\) stored in the PCM memory: · \*\*P0456 \- EVAP System Small Leak. · P1611 \- Supercharger Bypass Valve Position Sensor 1 Circuit High. · P0513 \- Invalid Skim Key.\*\* · P0300 \- Multiple Cylinder Misfire \(manual transmission applications only\). · P1613 \- Turbocharger/Supercharger Boost Pressure Sensor/Mass Air Flow Sensor Correlation. · P2227 \- Barometric Pressure Circuit Performance. · P1217 \- Active Exhaust Valve 1 Performance. · P121B \- Active Exhaust Valve 2 Performance. \*\*The P0513 code is set during remote starting the vehicle and nearly simultaneously pressing the Key Fob button against the Keyless Ignition Node \(KIN\) causing an engine stall.\*\*
- [10076306](https://open.wenmarpro.com/bulletins/10076306), 2016-07-07: 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.