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Service bulletins for the 2018 Jeep Wrangler

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

716 on file from NHTSA, as of 2026-10-19.

About P0456 on the 2018 Jeep Wrangler: what the code means, and the bulletins and recalls about the same components.

By type

By component

By trouble code

Only bulletins with trouble code: P0456 are shown. Show all

Bulletins, newest first
18048232023-05-30. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18018202023-01-09. Service bulletin. BACK OVER PREVENTION; ELECTRICAL SYSTEM; EXTERIOR LIGHTING; FUEL SYSTEM, GASOLINE. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs: P04FC - Crankcase Ventilation System Performance. P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update: Electric vacuum pump (EVP) update. Fan noise reduction.
18144222022-11-07. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs: P0335 - Crankshaft Position Sensor Circuit. P0339 - Crankshaft Position Sensor Intermittent. P2C90 - Crankcase Ventilation System - Hose "A" Disconnected. P04FC - Crankcase Ventilation System Performance. P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update: Electric vacuum pump (EVP) update. Fan noise reduction.
18014202022-10-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). 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 that one or more of the following DTCs have been set:P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P04FC - Crankcase Ventilation System Performance(APAC, EMEA and LATAM Only). P2453 - Particulate Filter Pressure Sensor "A" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P245F - Particulate Filter Pressure Sensor "B" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P0456 - EVAP System Small Leak. If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). P050B - Cold Start Ignition Timing Performance(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). Customers may comment on one or more of the following:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements also included in this update:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18018202022-09-26. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs: P04FC - Crankcase Ventilation System Performance. P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update: Electric vacuum pump (EVP) update. Fan noise reduction.
18092192022-09-15. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technicianmay find one or more of the following Diagnostic Trouble Codes (DTCs):P06EF - Engine Restart Performance. P0456 - EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification test (SLVT)to determine if a leak is present in the system. Customers may experience one or more of the following:Excessive blower fan noise when the A/C is on MAX output. Intermittentrough idle or idle surging, when coming to a stop(Automatic transmission equipped vehicles only). Random Electronic Stability Control (ESC) lamp illuminates in the InstrumentPanel Cluster (IPC). Driving at vehicle speeds while in first gear and shifting into neutral, amessage "Shift to 1st gear not allowed" message appears in the Electronic Vehicle Information Center (EVIC) when conditions are not met(Manual transmission equipped vehicles only). 3 km (2 mph) difference between cruise set speed versus actual displayspeed. During cold vehicle operation and the use of cruise control on vehicles equipped with an automatic transmission, the engine RPMs may dropbelow idle speed while cruise control is engaged, this may occur if the customer presses the accelerator pedal to achieve a vehicle speedgreater than the cruise control speed and then releasing it. Radio or IPC may reboot (flash off/flash on) during an Engine Stop Start(ESS) shutdown in cold conditions with a battery temperature below -12°C (10°F).
18089192022-09-15. Service bulletin. ENGINE AND ENGINE COOLING. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18-036-212021-05-24. Service bulletin. FUEL SYSTEM, GASOLINE; BACK OVER PREVENTION; ELECTRICAL SYSTEM; EXTERIOR LIGHTING; SERVICE BRAKES. 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 that one or more of the following DTCs have been set:P02EE - Cylinder 1 Injector Circuit Performance(APAC, EMEA and LATAM Only). P02EF - Cylinder 2 Injector Circuit Performance(APAC, EMEA and LATAM Only). P02F0 - Cylinder 3 Injector Circuit Performance(APAC, EMEA and LATAM Only). P02F1 - Cylinder 4 Injector Circuit Performance(APAC, EMEA and LATAM Only). P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P04FC - Crankcase Ventilation System Performance(APAC, EMEA and LATAM Only). P2453 - Particulate Filter Pressure Sensor "A" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter(GPF)). P245F - Particulate Filter Pressure Sensor "B" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF)). P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). P050B - Cold Start Ignition Timing Performance(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). Customers may comment on one or more of the following:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. The following software enhancements are also included in this update:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-018-20 REV. A2020-08-24. Service bulletin. POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs: P04FC - Crankcase Ventilation System Performance. P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update: Electric vacuum pump (EVP) update. Fan noise reduction.
18-014-20 REV. B2020-07-27. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). 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 that one or more of the following DTCs have been set:P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P04FC - Crankcase Ventilation System Performance(APAC, EMEA and LATAM Only). P2453 - Particulate Filter Pressure Sensor "A" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P245F - Particulate Filter Pressure Sensor "B" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P0456 - EVAP System Small Leak. If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). P050B - Cold Start Ignition Timing Performance(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). Customers may comment on one or more of the following:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements also included in this update:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-014-20 REV. A2020-05-26. Service bulletin. FUEL SYSTEM, GASOLINE; EXTERIOR LIGHTING; ELECTRICAL SYSTEM; BACK OVER PREVENTION. 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 that one or more of the following DTCs have been set:P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient emperatures. Software enhancements include:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-014-20 REV. A2020-05-18. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). 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 that one or more of the following DTCs have been set:P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient emperatures. Software enhancements include:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-014-20 REV. A2020-04-27. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. 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 that one or more of the following DTCs have been set:P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient emperatures. Software enhancements include:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-018-202020-04-06. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following Diagnostic Trouble Code (DTC):P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update:Electric vacuum pump (EVP) update. Fan noise reduction.
18-014-202020-04-06. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. 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 that one or more of the following DTCs have been set:P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT)to determine if a leak is present in the system. P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements include:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
18-034-19 REV. A2020-01-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following DTCs:P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. P0456 - EVAP System Small Leak. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update:Electric vacuum pump (EVP) update. Fan noise reduction.
18-092-192019-12-16. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technicianmay find one or more of the following Diagnostic Trouble Codes (DTCs):P06EF - Engine Restart Performance. P0456 - EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification test (SLVT)to determine if a leak is present in the system. Customers may experience one or more of the following:Excessive blower fan noise when the A/C is on MAX output. Intermittentrough idle or idle surging, when coming to a stop(Automatic transmission equipped vehicles only). Random Electronic Stability Control (ESC) lamp illuminates in the InstrumentPanel Cluster (IPC). Driving at vehicle speeds while in first gear and shifting into neutral, amessage "Shift to 1st gear not allowed" message appears in the Electronic Vehicle Information Center (EVIC) when conditions are not met(Manual transmission equipped vehicles only). 3 km (2 mph) difference between cruise set speed versus actual displayspeed. During cold vehicle operation and the use of cruise control on vehicles equipped with an automatic transmission, the engine RPMs may dropbelow idle speed while cruise control is engaged, this may occur if the customer presses the accelerator pedal to achieve a vehicle speedgreater than the cruise control speed and then releasing it. Radio or IPC may reboot (flash off/flash on) during an Engine Stop Start(ESS) shutdown in cold conditions with a battery temperature below -12°C (10°F).
18-089-192019-12-16. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
18-041-192019-07-15. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the Powertrain Control Module (PCM) with thelatest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or moreof the following DTCs have been set: P0456 - EVAP System Small Leak(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience: Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements include:Electric vacuum pump (EVP) update. Fan noise reduction. Low speed pre ignition (LSPI) update.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.