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Service bulletins for the 2021 Peterbilt 579

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.

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

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Bulletins, newest first
24PBE_KWE2026-03-05. Service bulletin. ELECTRICAL SYSTEM. The Parts section has been updated to clarify that freight charges for safety recall orders should not be passed on to the end customer.
45-0702026-02-05. Service bulletin. ENGINE. Procedure pictures updated for clarity. 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.
46-0192025-12-05. Service bulletin. UNKNOWN OR OTHER. Repair procedures and warranty information for model 520EV are now available. 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.
01-0902025-12-05. Service bulletin. ENGINE. Repair procedures and warranty information for model 520EV are now available. 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.
24PBE2025-12-05. Service campaign. ELECTRICAL SYSTEM; POWER TRAIN. The right-hand shift stalk may have an improper wire harness terminal crimp within the wire harness connector. 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.
E3112025-09-03. Other. ENGINE; POWER TRAIN. Condition, Chassis Affected, and Warranty sections updated with the following verbiage “E311 must be flagged and open in 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.
E3182025-07-02. Service bulletin. ENGINE; FUEL/PROPULSION SYSTEM. Newly designed fuel injectors are available for EPA2021 compliant PACCAR MX-series engines to optimize engine performance. Injectors must be replaced as a full set (6 injectors) and associated software must be updated at the same time.
T016 / 26-0402025-06-05. Service bulletin. POWER TRAIN. T016: Warranty section updated to include 0.5 hours for test drive. 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.
98-0302025-06-05. Service bulletin. ELECTRICAL SYSTEM. 5/29/2025: A new Ethernet Multiplexed Architecture (EMUX) Service Tool Kit service manual (SM034-022) has been released 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.
46-0162025-05-06. Service campaign. ELECTRICAL SYSTEM. 4/29/2025: Campaign A software update is available for 520EV and 579EV Battery Electric Vehicles. 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.
E3272025-03-04. Emissions. ELECTRICAL SYSTEM; ENGINE. "Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. 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.
46-0132025-03-04. Service campaign. ELECTRICAL SYSTEM. Certain Peterbilt 579EV and 520EV Battery Electric Vehicles were built prior to the availability of certain labels and Low Voltage Distribution System (LVDS) Components. Affected chassis will be inspected and necessary components will be installed.
24PBL2025-02-05. Service bulletin. FORWARD COLLISION AVOIDANCE: WARNINGS; UNKNOWN OR OTHER; ELECTRICAL SYSTEM. Safety Recall Updated software and procedures are now available. 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
32-0252024-12-03. Service bulletin. ENGINE. Info Only Unnecessary starter replacements can result from customer complaints regarding engine starting issues. 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.
46-0112024-12-02. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Some 579EV and 520EV BEV trucks may have loose or improperly torqued ESS gland nuts. This may cause an intermittent warning light on the dash display.
7-7002024-11-05. Warranty extension. POWER TRAIN; ENGINE. 7/700 Service Agreement - Letter Only.
E2902024-10-05. Service bulletin. FUEL/PROPULSION SYSTEM. FIX-AS-FAIL Updated to include EPA2024 compliant engines. 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.
98-0302024-10-05. Service campaign. ELECTRICAL SYSTEM. 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.
46-0142024-10-05. Service bulletin. UNKNOWN OR OTHER. Information Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty Battery Electric Vehicles.
E3162024-09-10. Service bulletin. ENGINE. Bulletin updated to include oil pan drain plug in parts list and incorporated QR code to direct dealers to informational resources for new Programmable Torque Tool.
46-001 HVAC Update2024-09-10. Other. ELECTRICAL SYSTEM. BEV Phase 2 tools have been added to the BEV required tools lists.
16-0442024-08-02. Service bulletin. SUSPENSION. Fix As Fail The height control valve (HCV) rod on vehicles with low air leaf suspensions is prone to toggling over center during rough road conditions. 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.
36-1912024-06-04. Service bulletin. VISIBILITY/WIPER. Information Only Vehicles equipped with Digital Vision System (DVS) Mirror Mounted Cameras, that do not have optional 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.
34-0952024-03-04. Service bulletin. STRUCTURE:FRAME AND MEMBERS:UNDERBODY SHIELDS; ELECTRICAL SYSTEM; ELECTRICAL SYSTEM:WIRING:FRONT UNDERHOOD. Fix As Fail – Dimensions and instructions are available for trimming the radiator recirculation shields to alleviate possible rub to the hood harness. (ARC 1/22/24)
34-0952024-02-06. Service bulletin. ELECTRICAL SYSTEM. Fix As Fail – Dimensions and instructions are available for trimming the radiator recirculation shields to alleviate possible rub to the hood harness.

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