JEEP
18-034-25
Manufacturer communications
- Publication date
- 2025-06-25
- Received by NHTSA
- 2025-07-02
- NHTSA record numbers
- 11020109
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 exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs):
• P0420 - Catalyst System Efficiency Below Threshold Bank 1.
• P0430 - Catalyst System Efficiency Below Threshold Bank 2.** **In addition, the customer may experience one or more of the following:
• Vehicle fails emissions inspection testing due to OBD catalyst monitor readiness.**
• Actual fuel economy reporting may not match the Instrument Panel Cluster (IPC). Other software enhancements:
• Calibration update to address EVAP system emissions monitor readiness status accuracy This bulletin involves reprogramming the PCM with the latest available software.
• P0420 - Catalyst System Efficiency Below Threshold Bank 1.
• P0430 - Catalyst System Efficiency Below Threshold Bank 2.** **In addition, the customer may experience one or more of the following:
• Vehicle fails emissions inspection testing due to OBD catalyst monitor readiness.**
• Actual fuel economy reporting may not match the Instrument Panel Cluster (IPC). Other software enhancements:
• Calibration update to address EVAP system emissions monitor readiness status accuracy 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
P0420Catalyst System Efficiency Below Threshold Bank 1Check 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 | 2019 |