Service bulletin 18-037-21

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10194047
Published by NHTSA	2021-05-24
Manufacturer's number	18-037-21
Manufacturer's date	2021-04-15
NHTSA component	EXTERIOR LIGHTING; BACK OVER PREVENTION; FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM; SERVICE BRAKES

NHTSA's summary

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). P012A - Turbocharger/Supercharger Inlet Pressure Sensor 1(APAC, EMEA and LATAM Only). P012C - Turbocharger/Supercharger Inlet Air Pressure Sensor 1 Circuit Low(APAC, EMEA and LATAM Only). P012D - Turbocharger/Supercharger Inlet Air Pressure Sensor 1 Circuit High(APAC, EMEA and LATAM Only). P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P06EF - Engine Restart Performance. P04FC - Crankcase Ventilation System Performance. P050B - Cold Start Ignition Timing Performance. P0128 - Thermostat Rationality. P0456 - EVAP System Small Leak. If DTC P0456 is present, use the wiTECH Small Leak Verification Test (SLVT) to determine if there is a leak in the system. The following software enhancement is also available in this update:Enable soot retention for vehicles equipped with Gasoline Particulate Filter (GPF). Technicians may also experience the following:Unable to read data information from the OBD II connector when using a generic scan tool(APAC Only).

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Brakes, Driver assistance, Electrical system, Fuel system, Lighting, Backup camera

Trouble codes named

P0128, P012A, P012C, P012D, P02EE, P02EF, P02F0, P02F1, P0456, P04FC, P050B, P06EF, P2C90

Vehicles listed
JEEP WRANGLER	2019

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
24V676000	2024-09-12. BACK OVER PREVENTION: SENSING SYSTEM: CAMERA; EXTERIOR LIGHTING:BRAKE LIGHTS
20V191000	2020-09-10. BACK OVER PREVENTION: SENSING SYSTEM: CAMERA

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
0300224	2024-03-18. Service bulletin. Front and Rear Axle Sensor Kit Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that the following Diagnostic Trouble Code (DTC) has been set: ? C1451-11 - Service Axle Locker System Customers may also comment on a Service Axle Locker message displayed in the Electronic Vehicle Information Center (EVIC) for this condition.
S2319000007	2024-01-08. Service bulletin. Squeak Noise From Dash Area When Turning The Steering Wheel.
9003357	2024-01-02. Service bulletin. ADAPTER, Engine Oil Filter (Pentastar V6) For all 2014MY replace the Oil Filter Adapter (OFA). For any other MY (with mileage above 30,000) review and follow instructions from STAR Online S1809000007 REV. C available on Dealer Connect. Also, consider the following: 1) Remove OFA 2) Replace only the oil inlet O-ring and gaskets (seals kit in SOL above). 3) Re-install the OFA. For 2023MY and beyond use black O-ring. For 2022MY and prior use red O-ring. Note: When replacing OFA, it may be necessary to transfer the Oil Temp/Pressure Sensor from the old OFA to the new OFA.
9100134	2024-01-02. Service bulletin. Engine When replacing a GMET4 long block from a 2021 JL or older, you will need to carry over the injector wiring harness from the original engine, and the Fuel pressure sensor should be replaced with part number: 68212572AB.
9100247	2023-12-18. Service bulletin. ERG Hydraulic Tensioner Before replacing any FEAD components, please check FEAD belt layout as per the engine sales code. Customer complaint may include a noise from under the hood described as a squeal, screech, squeak, chirp or belt-related noise and/or noisy tensioner/pulley. Please refer to SOL# S2309000007.
S1808000152	2023-10-02. Service bulletin. CEL (Check Engine Lamp) Illuminated, P057B Brake Pedal Position Sensor Performance
9100133	2023-07-31. Service bulletin. ROCKER ARM ASSY - ROLLER ROCKER Case 1.- Before replacing the intake or exhaust rocker arms due to an abnormal ticking noise, please check that the INTAKE Hydraulic Lash Adjusters are not "collapsed". If a collapsed INTAKE HLA is found, replace all INTAKE HLAs on the suspect cylinder head (no need to replace rocker arms). The noise can occur at low or high RPMs, and at low or high temperatures. There are no Diagnostic Trouble Codes (DTC)s present. Case 2.- If the INTAKE camshaft or INTAKE rocker arm has excessive wear on the high lift profile (Rocker arm: slider, Camshaft: central lobe), replace the intake camshaft (1) in that cylinder head and all intake rocker arms (6).
08-038-23	2023-02-13. Service bulletin. Radio Over The Air JR34.3 Updating to JR34.32.Software Version Customers may experience one or more of the following: Not be able to use Mobile Wi-Fi upon start up. Hotspot gives a no Internet connection message on phone when trying to connect to a device. This bulletin provides information regarding the latest Firmware Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. The radio software will be updated from JR34.3 to JR34.32. NOTE: National launch for this FOTA update is expected to begin February 20, 2023.
0809321	2023-01-17. Service bulletin. UAS, UAQ, UCS, UAV, UCV and UCQ Radio Over The Air Software Version Updates This bulletin provides information regarding the latest Flash Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. This is part of a two step FOTA update, first update brings software level to 22.61 and this second FOTA update will take the software to 22.64. National launch for this second step is May 24, 2021. Customers may experience one or more of the following:Navigation is incorrect or can not calculate route. GPS locations is inaccurate. Uconnect radio apps are all inoperable. Backup camera screen is blue (DT and KL). Green horizontal lines appear across screen (DT and KL). Anti-theft code request message. Backup camera screen is blank. Lines appear across screen. Radio control screen is blank or locked. Radio reset intermittently. Unable to adjust audio volume. Unable to switch modes between AM, FM, SAT or Media. In addition the following enhancements are included in this update:Carplay® connectivity improvement. Improvement to Bluetooth® phone pairing. Bluetooth devices unresponsive. Improved sound quality when using a Bluetooth phone.
2400721	2023-01-17. Service bulletin. Flash: HVAC Diagnostic and System Updates This bulletin involves reprogramming the HVAC control module with the latest available software. The customer may notice one or more of the following:Intermittent change of smell or humidity level in vehicle. An intermittent blast of warm air when A/C is on. Intermittent increase of outside air through the HVAC system. In addition, the following software enhancement is also available:Improvements for customer concerns of 'cabin too warm', specifically in the mid ambient temperature range 4.5-15.5 °C (40-60 °F).