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P0456 on the 2019 Jeep Grand Cherokee

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 P0456
18-035-252025-07-02. Service bulletin. 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.** ● P0441 - EVAP Purge System Performance (for North America and Mexico markets only). ● P0456 - EVAP System Small Leak. NOTE: If DTC P0456 is present, use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. **In addition, the customer may experience the following: ● Vehicle fails emissions inspection testing due to OBD catalyst monitor readiness.** This bulletin involves reprogramming the PCM with the latest available software.
18100232024-01-08. Service bulletin. Flash: Powertrain Control Module (PCM) Updates 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) has been set: ?**P0441 - EVAP Purge System Performance (for North America and Mexico markets only).** ? P0456 - EVAP System Small Leak. NOTE: ** If DTC P0456 is present, use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. ** This bulletin involves reprogramming the PCM with the latest available software.
18100232023-10-30. Service bulletin. Flash: Powertrain Control Module (PCM) Updates 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) has been set: ?**P0441 - EVAP Purge System Performance (for North America and Mexico markets only).** ? P0456 - EVAP System Small Leak. NOTE: ** If DTC P0456 is present, use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. ** This bulletin involves reprogramming the PCM with the latest available software.
18048232023-05-30. Service bulletin. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18089192022-09-15. Service bulletin. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18-009-202020-04-06. Service bulletin. Flash: Powertrain Control Module (PCM) and Transmission Control Module (TCM) Updates This is a coordinated bulletin that involves reprogramming the PCM and TCM,at the same time, with the latest available software.Both the PCM and TCM must be up to date for these changes to be effective. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following DiagnosticTrouble Code (DTC):P0456 - EVAP System Small Leak. Customers may also experience the following:Extended engine crank times. The following improvement is also included:Transmission coast-down shift quality improvements.
18-089-192019-12-16. Service bulletin. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18-057-19 REV. B2019-12-02. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following Diagnostic Trouble Code (DTC) has been set: P0456 - EVAP System Small Leak. Customer or technician may also experience the following:Unable to read data information from the OBDII connector when using a generic scan tool.(APAC only).

8 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.