JEEP
18-051-26
Manufacturer communications
- Publication date
- 2026-04-18
- Received by NHTSA
- 2026-04-22
- NHTSA record numbers
- 11031456
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 - In Active or Stored status set during cold start catalyst heating.
• P0301 - Cylinder 1 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0302 - Cylinder 2 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0303 - Cylinder 3 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0304 - Cylinder 4 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0305 - Cylinder 5 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0306 - Cylinder 6 Misfire - In Active or Stored status set during cold start catalyst heating.
• P2066 - Fuel Level Sensor 2 Performance.
• P152F - Engine Hood Switch 2 / Engine Hood Switch 1 Correlation.**
• C053D - Brake Pressure Sensor 1 Performance. **Customers may also comment on one or more of the following:
• Check engine illuminates when fueling the vehicle while the engine is running.
• Vehicle has a noticeable misfire.
• Vehicle idles rough.
• Engine noise. NOTE: Noise is heard coming from the valvetrain.** **In addition, the following software enhancement is available:
• Update to prevent customers from driving their vehicles while the Electric Park Brake (EPB) is engaged. Engine torque will be limited to prevent the Rear Drive Unit from being damaged. NOTE: Previously, the EPB would remain engaged without any torque limit which could lead to the Rear Drive Unit being damaged/broken.** This bulletin involves reprogramming the PCM with the latest available software.
• **P0300 - Multiple Cylinder Misfire - In Active or Stored status set during cold start catalyst heating.
• P0301 - Cylinder 1 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0302 - Cylinder 2 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0303 - Cylinder 3 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0304 - Cylinder 4 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0305 - Cylinder 5 Misfire - In Active or Stored status set during cold start catalyst heating.
• P0306 - Cylinder 6 Misfire - In Active or Stored status set during cold start catalyst heating.
• P2066 - Fuel Level Sensor 2 Performance.
• P152F - Engine Hood Switch 2 / Engine Hood Switch 1 Correlation.**
• C053D - Brake Pressure Sensor 1 Performance. **Customers may also comment on one or more of the following:
• Check engine illuminates when fueling the vehicle while the engine is running.
• Vehicle has a noticeable misfire.
• Vehicle idles rough.
• Engine noise. NOTE: Noise is heard coming from the valvetrain.** **In addition, the following software enhancement is available:
• Update to prevent customers from driving their vehicles while the Electric Park Brake (EPB) is engaged. Engine torque will be limited to prevent the Rear Drive Unit from being damaged. NOTE: Previously, the EPB would remain engaged without any torque limit which could lead to the Rear Drive Unit being damaged/broken.** 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
C053DBrake Pressure Sensor 1 PerformanceJeep
P0300Multiple Cylinder Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0301Cylinder 1 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0302Cylinder 2 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0303Cylinder 3 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0304Cylinder 4 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0305Cylinder 5 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P0306Cylinder 6 Misfire - In Active or Stored status set during cold start catalyst heatingJeep
P152FEngine Hood Switch 2 / Engine Hood Switch 1 CorrelationJeep
P2066Fuel Level Sensor 2 PerformanceCheck 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 | GRAND CHEROKEE | 2023 |
| Jeep | GRAND CHEROKEE L | 2023 |