# P0303 on the 2023 Jeep Wrangler

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 P0303

- [11031453](https://open.wenmarpro.com/bulletins/11031453), 2026-04-22: 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 \(DTCs\): ● P0300 \- Multiple Cylinder Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0301 \- Cylinder 1 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0302 \- Cylinder 2 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0303 \- Cylinder 3 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0304 \- Cylinder 4 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0305\-00 \- Cylinder 5 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0306\-00 \- Cylinder 6 Misfire \(Active or Stored status set during cold start catalyst heating\). Customers may also comment on one or more of the following: ● The vehicle has a rough idle. ● The engine has a miss. ● Noisy valvetrain. This bulletin involves reprogramming the PCM with the latest available software.
- [11031451](https://open.wenmarpro.com/bulletins/11031451), 2026-04-22: 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 \(DTCs\): ● \*\*P0300 \- Multiple Cylinder Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0301 \- Cylinder 1 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0302 \- Cylinder 2 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0303 \- Cylinder 3 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0304 \- Cylinder 4 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0305\-00 \- Cylinder 5 Misfire \(Active or Stored status set during cold start catalyst heating\). ● P0306\-00 \- Cylinder 6 Misfire \(Active or Stored status set during cold start catalyst heating\).\*\* ● P08A6 \- Gear Lever Position Sensor System \- Multiple Sensor Correlation. ● P152F \- Engine Hood Switch 2 / Engine Hood Switch 1 Correlation. ● P1129 \- Closed Loop Fueling Not Achieved \- Bank 2 Upstream. ● P0152\-02 \- O2 Sensor 2/1 Circuit High. ● P0158\-02 \- O2 Sensor 2/2 Circuit High. ● P2504 \- Charging System Output High. ● P0563 \- Battery/System Voltage High. Customers may also comment on one or more of the following: ● \*\*The vehicle has a rough idle. ● The engine has a miss. ● Noisy valvetrain. ● "Service Transmission" message in the Instrument Panel Cluster \(IPC\) due to clutch slip detection with the transfer case in neutral. NOTE: Some customers may experience wheel spin or traction loss. In these situations, the Powertrain Control Module \(PCM\) may interpret the event as excessive clutch slip. To prevent potential clutch damage, a message may be displayed in the Instrument Panel Cluster \(IPC\).\*\* ● Clutch is overheating. ● Clutch is slipping on engagement. ● Inability to accelerate uphill. M18 FSAR\-TSB\-7162 \-2\- ● Vehicle does not start. ● Vehicle is stuck in limp\-home mode
- [11018482](https://open.wenmarpro.com/bulletins/11018482), 2025-05-20: "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. "
- [10236946](https://open.wenmarpro.com/bulletins/10236946), 2023-05-30: Flash: Powertrain Control Module \(PCM\) Updates Customers may experience a Malfunction Indicator Lamp \(MIL\) illumination. Upon further investigation, a technician may find one or more of the following Diagnostic Trouble Codes \(DTCs\) have been set: ? P016F \- Closed Loop Fuel Pressure Control At Limit \- Pressure Too Low. ? P025C \- Fuel Pump Module Control Circuit Low. ? 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. ? P0403\-00 \- EGR Control Circuit Open \(Disabled Fault\). ? P208B \- Reductant Pump 1 Control Performance. Other Software enhancements: ? Low speed engine idle improvements. ? Improved engine restart performance and torque response during low fuel level and/or hot ambient conditions. This bulletin involves reprogramming the PCM with the latest available software.