Service bulletin 1803621

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	10221200
Published by NHTSA	2022-09-26
Manufacturer's number	1803621
Manufacturer's date	2021-04-15
NHTSA component	EXTERIOR LIGHTING; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE; BACK OVER PREVENTION; ELECTRICAL SYSTEM; SERVICE BRAKES, HYDRAULIC; FUEL SYSTEM, GASOLINE

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 f 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.

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, Transmission and driveline, Automatic transmission, Backup camera, Transmission control module

Vehicles listed
JEEP WRANGLER	2018

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
18V280000	2018-05-01. POWER TRAIN:AUTOMATIC TRANSMISSION

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.
S1808000152	2023-10-02. Service bulletin. CEL (Check Engine Lamp) Illuminated, P057B Brake Pedal Position Sensor Performance
S2325000006	2023-08-21. Service bulletin. Customer complaint may include a MIL-on or check engine lamp on condition.
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).
S1808000152	2023-04-17. Service bulletin. CEL (Check Engine Lamp) Illuminates, Recent PCM Replace or Flash Update Performed, Diagnostic Trouble Codes (DTCs) P057B Brake Pedal Position Sensor Circuit Performance, P1572 Brake Pedal Stuck, C0042-54 Brake Pedal Missing Calibration
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).