JEEP
18-048-26
Manufacturer communications
- Publication date
- 2026-04-17
- Received by NHTSA
- 2026-04-22
- NHTSA record numbers
- 11031453
Manufacturer summary
Original wording in English
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.
• 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.
Reported code forms
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
Jeep
P0300Multiple Cylinder Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0301Cylinder 1 Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0302Cylinder 2 Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0303Cylinder 3 Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0304Cylinder 4 Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0305-00Cylinder 5 Misfire (Active or Stored status set during cold start catalyst heating)Jeep
P0306-00Cylinder 6 Misfire (Active or Stored status set during cold start catalyst heating)Check vehicle applicability
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Jeep | WRANGLER | 2023 |