2021 Peterbilt 579 TSBs

This update provides customers with additional time to service their trucks before a DEF-related derate occurs. The software is being offered to customers in alignment with recently updated regulatory agency guidance.

This update provides customers with additional time to service theirtrucks before a DEF-related derate occurs. The software is being offered to customers in alignment withrecently updated regulatory agency guidance."

policy."

This retrofit should have been completed by 5/15/2022 per the Action section of the bulletin. However, trucks still open in SIR are still eligible for the repairs.

crank-mounted fan drive may experience a short due to chafing or water ingress, affecting fan drive operation.

engines.

This failure can cause significant damage to the engine. New intake valve springs will be installed.

system inspection process for all engine air intake system components.

When troubleshooting Cummins X15 fault codes 555 or 556, follow this additional testing, inspection, and documentation procedure to help identify the root cause of dusted engines. This is not a stand-alone process but must be used alongside Cummins troubleshooting steps. Cummins Quickserve will reference this bulletin for fault codes 555 or 556.

Loss of communication between the right-hand shift stalk and the vehicle may result in the vehicle being disabled after it comes to a stop, thereby increasing the risk of crash or injury. A warning will appear on the dash display when communication is lost, including transmission or engine warnings, ! next to DNR/DNRP indicator, - in the DNR/DNRP indicator, and/or chimes, depending upon whether you are operating a diesel/gas or battery electric vehicle.

Injectors must be replaced as a full set (6 injectors) and associated software must be updated at the same time.

PCI-2 software on these chassis must be reverted from NA202 to NA201 (Pack 2 injectors) or from NA206 to NA191 (Pack 1 injectors) to prevent incorrect STOP lamp display.

A new Starter Troubleshooting Guide has been created to provide a comprehensive list of starting system checks, which should reduce unnecessary starter replacements and associated warranty claims. Engine starting system warranty claims now require a completed Starter Checklist, a Battery Pack Midtronics Report, and a Cable Drop Midtronics Report. Claims filed without these documents may be denied.

Fuel Filters must be changed before first cleaning. EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Discard any previous versions of E290 procedures always use the most current document from the link in the bulletin.

With full suspension articulation, HCV bracket flexes and toggles over center the HCV linkage, which results in either deflated airbags or makes them unable to inflate. Fix-as-fail start date is 07/30/2024.

contamination that occurred during manufacturing. SCR Catalyst assemblies will be inspected and replaced as necessary.

application and/or under torqued and could become loose and/or fail. Procedures are available to replace and properly torque the hardware.

.Debris and contaminants introduced into the high-pressure fuel system. .Denial of warranty claims for injector and/or fuel system faults. .Misfire, rough running, engine knock, and other associated faults and symptoms. Correct fuel filter procedures are outlined in attached service documentation.

application and/or under torqued and could become loose and/or fail. Procedures are available to replace and properly torque the hardware.

This is a one-time reimbursement. Only customers who have received E290 injector cleaning qualify for this reimbursement. See bulletin for limits and purchase tracking requirements.

display incorrect restriction levels. The virtual gauge will be temporarily disabled until are vised sensor strategy is developed.

Broken oil valve tabs can cause oil flow obstruction to critical engine parts, resulting in serious engine damage. Customers that do not receive this repair may be responsible for progressive engine damage caused by broken oil bypass valve tabs.

Cummins X15, X12, ISX12, ISX12N, L9N, PX-7, and PX-9 engines The technology will leverage the existing Remote Diagnostic cs hardware to deliver secure software updates remotely. This will reduce downtime and save on maintenance costs for eligible vehicles.

(HCV) arm may be rubbing on other components when the bend in the arm is facing outboard. Flipping the bend in the HCV arm inboard prevents the rub.

wiring harness.

Service

weather.

The resulting torque issue could affect the EPA21 MX-11 and MX-13 Oil Pan and/or the Exhaust Manifold.

to identify which of these engines are in a chassis.

Crossmember mounted Hill Start Assist valve may not have sufficient clearance to the rear axle, resulting in hose or fitting damage. Damage could cause the loss of rear brake signal, resulting in reduced braking capability and increasing the risk of a crash.

Cummins Recall C2402.

control unit (VECU2) and digital display (DD). Steps have also been added to the PACCAR Common Rail Injection 2 (PCI2) software verification.

Certain Peterbilt 579EV and 520EV chassis have the First Responder Guide (FRG) label incorrectly showing the cut loop on the wrong side and are missing the Low Voltage Battery Disconnect Switch and Do Not Jump Start labels. These labels are now available for installation.

to provide general use information. The new EMUX Service Tool Kit improves cab & chassis electrical troubleshooting efficiency, while reducing risk of component damage. 4/29/2025: The Ethernet Multiplexed Architecture (EMUX) Service Tool Kit and individual kit components are now available to order. Dealers that have received their first kit may order an additional kit. The EMUX Service Tool Kit Part number has been updated to match OEM drawings (P74-1045-001). Individual kit component part numbers can be found in the Reference Bill of Materials sheet. The new EMUX Service Tool Kit improves cab & chassis electrical troubleshooting efficiency, while reducing risk of component damage. Information Only New diagnostic tool is required to support PACCAR Ethernet Multiplexed Architecture (EMUX). The EMUX Service Tool Kit will help improve cab & chassis electrical troubleshooting efficiency, while reducing the risk of component damage.

This software update corrects or improves certain functions. Software update procedures have been revised. Campaign start date is 12/05/2024. Campaign A software update is available for 520EV and 579EV Battery Electric Vehicles. This software update corrects or improves certain functions. Campaign start date is 12/05/2024.

Low Voltage Distribution System (LVDS) Components. Affected chassis will be inspected and necessary components will be installed.

The EMUX Service Tool Kit will help improve cab & chassis electrical troubleshooting efficiency, while reducing the risk of component damage.

Vehicles.

(ARC 1/22/24)

possible rub to the hood harness.

Pressure Sensors for MX-13 -2, EMY19 Per Environment and Climate Change Canada (ECCC) regulations and guidance (Canadian Environmental Protection Act, 1999 (CEPA)), a letter has been provided to owners of Canadian registered chassis that provides a list of emissions components that have been reported (to ECCC) as having a defect.

causing possible damage.

Reinforcement brackets secure the connection and prevent separation.

experience battery movement on the side where the single battery resides. This bulletin contains a procedure to fabricate a bracket to hold this battery in place.

US registered, model year 2021 579 chassis. The parameter can be correctly set by reflashing the VECU with updated software.

As a temporary solution, after PACCAR confirms a DEF sensor is not available, a temporary software update will allow a vehicle to continue operation with a failed DEF sensor by disabling the DEF sensor diagnostics.

Software update required.

A VECU software update is available to resolve the issue.

Updated VECU software is available to resolve the issue.

appropriate tests for battery warranty are performed in order to prevent battery warranty claims filed with incorrect or incomplete information.

03/6/2006 to 1/20/2020, the clamps that secure the SOC exhaust stacks may not be tightened properly. This may allow the exhaust stack to rotate and contact the cab or sleeper.

latest prognostics bulletin verbiage.

The bulletin will be updated when more information is available."

procedure has been updated with additional note boxes for clear instructions. PB: The repair procedure has been updated with additional note boxes for clear instructions."

This is not a stand-alone procedure. Cummins Quickserve troubleshooting will specify the use of these procedures while troubleshooting specific fault codes.

Failure to do so may result in warranty claim denial. See the procedure section for more details.

the end customer.

Service Information Record (SIR) at the time of RO open date to qualify. Also, Through Standard Warranty or any applicable active Extended Warranty verbiage was removed from Warranty section.

Recommended Repair T016C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes. 26-040: Warranty section updated to include 0.5 hours for test drive. Recommended Repair 26040C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes.

resources for new Programmable Torque Tool.

EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Refer to E300 for in-tank additive information.

Certain model year 2021 to 2024, 567 and 579 vehicles built from 06/22/2020 through 06/16/2023 were equipped with air tank bracket G11-6439-009mounted behind a fuel tank without a frame spacer. The air tank mounting U-bolt tips may be different lengths and could contact the fuel tank, which can result in a hole and the potential for a fuel leak. Leaking fuel may lead to an increased risk of a fire.

Removed in-tank additive references.

were equipped with air tank bracket G11-6439-009mounted behind a fuel tank without a frame spacer. The air tank mounting U-bolts are different lengths and may contact the fuel tank, which can result in a hole and the potential for a fuel leak. Leaking fuel may lead to an increased risk of a fire. At this time, parts are not yet available to complete the necessary repairs. Once parts become available, this bulletin will be updated.

This fuel filter set is available directly from a PACCAR dealership parts department.

This procedure also provides information to determine if it is necessary to replace the fuel injectors.

Gateway (PMG001) will experience severe 3G service degradation as early as January of 2022. Chassis currently utilizing 3G antennas as a primary antenna may experience this degradation.

A redesigned bracket can be purchased that relocates the marker bracket to the front fuel tank bracket to eliminate interference.

of injury while entering and exiting the cab. The repair procedure and parts information will be added when parts are available.

A parameter update, via Cummins Insite, restores proper DPF regeneration function.

housings.

left-hand or right-hand blind spotters, may set false Diagnostic Trouble Codes (DTC) 522490-9 or 522491-9. These DTCs can be ignored if corresponding blind spotter is not equipped. The next Digital Vision System Mirrors (DVS-M) software update will correct these false DTCs.

may experience bracket failure causing the bracket and camera to fall from the windshield.

fatigue from external forces such as reverse towing.

fender and the bottom of the trailer/equipment are susceptible to damage. The lack of clearance could result in cracked/broken quarter fenders or complete separation if undetected or un-remedied.

Washer pumps may fail to spray due to a clogged filter.

Vehicles built from 9/27/2019 through 2/06/2020 with windshield Julian date codes between 263 of 2019 and 031 of 2020 could be affected. Resolution is to replace any failed windshields with a delaminated seal.

Oil from the air shift cover of the PTO may leak into the air line, causing the EOA solenoid to become inoperative.

adapter harness with the improved harness and clear the DTCs.

Premature Main Drive Gear damage may occur due to clutch housing and main case countershaft bearing bore wear.

and main case countershaft bearing bore wear. A Clutch Housing Front Cover Kit will be installed to address the issue.

(LCA) fault codes leading to possible LCA hardware replacement.

lamp activation, no gear engagement from neutral, and/or DTC 511 FMI 7 or 10 is set. Resolution is to update the transmission software and calibrations.

codes leading to possible LCA hardware replacement.

2 chassis added to the chassis list. Peterbilt: Dealers should check the chassis list and SIR weekly for VIN changes. 10 chassis added to the chassis list."

midship one-piece aluminum crossmembers.

5 chassis have been added to the chassis list. The total chassis population is now 15,637.

The cab heater coolant system on Peterbilt 579EV and 520EV models may not deaerate properly, causing pump malfunctions and inadequate cab heating. Update coolant deaeration return line parts and procedures are now available to release trapped air back to the reservoir.

The HVAC may intermittently stop blowing cold air, typically after a truck restart. Driver may notice the system returns to normal after key cycle. The remedy is updating HVAC software.

Certain Vehicle Model Year 2021-2025 Peterbilt chassis configured for trailer towing require a software update for the Bendix EC80 ABS ECU. Software update procedures for certain Battery-Electric Vehicles (BEV) and EC80 ABS ECU part numbers are not yet available. This bulletin will be updated when software update procedures are available for these chassis. Safety Recall publish date: 1/10/25

The work brake (also known as winch brake) may unintentionally disengage during winching operations, releasing the service brakes, increasing the risk of crash or injury. The VECU software will be updated to correctly set the speed interlock parameter.

trucks, built between 4/13/2010 and 3/16/2020 and equipped with a flush mounted battery box, utilized rubber washers that could rub through and cause the aluminum box mounting tabs to rub directly on the steel frame brackets. This could result in cracked battery box mounting angles. Resolution is to add the reinforcement bracket(s) to affected vehicles.

This may cause an intermittent warning light on the dash display.

MUX switches, and Kick Panel.

the headlamps, fog lamps or turn signals are not on. This is non-compliant with Canadian Regulation CMVSS 108, which states that the DRLs must be on while the vehicle is in motion without certain other lamps being activated. This bulletin will be updated when a repair is available.

January 01, 2017 and July 06, 2020. Torsional vibration may stress the currently-installed brackets and cause them to fail near the bottom of the frame rail.

bracket.

The driver could be unaware of an issue with the methane detection system or excessive methane present, increasing the risk of a fire, crash and/or personal injury. The repair procedure will be added when it is available.