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Service bulletins for the 2020 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.

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

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
02-1772026-06-03. Service bulletin. ELECTRICAL SYSTEM. Troubleshooting procedures for 2.1m cab power windows are now available.
E3262026-05-06. Emissions. ENGINE; ELECTRICAL SYSTEM. EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines.
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.
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.
28-0012023-10-03. Service bulletin. ELECTRICAL SYSTEM. For all Peterbilt chassis equipped with an air shifted PTO. Oil from the air shift cover of the PTO may leak into the air line, causing the EOA solenoid to become inoperative.
36-0082023-06-03. Service bulletin. STRUCTURE; ELECTRICAL SYSTEM. Certain 579 chassis are eligible to receive production level Digital Display software, Digital Display, Lane Keep Assist MUX switches, and Kick Panel.
34-0962023-05-05. Service bulletin. SERVICE BRAKES, AIR; ELECTRICAL SYSTEM. Fix As Fail – All New Model 579 chassis with Bendix radar opti on may have a harness rub against the radiator that is causing possible damage.
32-0192023-03-01. Service bulletin. STRUCTURE; ELECTRICAL SYSTEM. Fix As Fail – Chassis that were manufactured with certain battery cable routing brackets may experience rubbing or chafing of the battery cables.
21PBN2022-12-05. Service bulletin. FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY; ELECTRICAL SYSTEM. 21PBN – LNG/CNG Methane Detecti on System Will Not Warn Operator if System Loses Power – NHTSA ID:21V00N, TC: 2021-793
34-0902022-03-04. Service bulletin. EQUIPMENT; EXTERIOR LIGHTING; ELECTRICAL SYSTEM. A frame mounted left-hand marker light bracket interferes with the rear fuel tank fill location. A redesigned bracket can be purchased that relocates the marker bracket to the front fuel tank bracket to eliminate interference.
21PBN2022-02-04. Service bulletin. FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY; ELECTRICAL SYSTEM; EQUIPMENT. Interim Safety Recall – Methane detection system will not warn the operator if the system loses power. 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.
42-0592021-12-03. Service bulletin. ELECTRICAL SYSTEM:PROPULSION SYSTEM:TRACTION MOTOR:CONTROLLER; ENGINE AND ENGINE COOLING:COOLING SYSTEM:FAN; ENGINE AND ENGINE COOLING. Non-Safety Campaign - Vehicles with a Cummins X15 engine and Horton fan drive may set Diagnostic Trouble Code (DTC) 6637 and/or 3838 due to fan speed that results in the fan remaining activated until the power is cycled. A new controller will resolve the issue.
52-0042021-08-05. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; ELECTRICAL SYSTEM:ADAS:BLINDSPOT:SOFTWARE. Fix-as-Fail: Radio does not mute when truck with auto trans is placed in reverse. Software flash resolves issue.
32-0172021-03-10. Service bulletin. ELECTRICAL SYSTEM. Non-Safety Campaign – The batteries may drain quickly due to the VECU not going to sleep. Updated VECU software is available to resolve the issue.
26-0372021-01-06. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN; EQUIPMENT ADAPTIVE/MOBILITY. Fix-As-Fail - Prior versions of Eaton Endurant transmission software may be prone to setting Linear Clutch Actuator (LCA) fault codes leading to possible LCA hardware replacement.
01-0792020-12-05. Service bulletin. ELECTRICAL SYSTEM. Fix as Fail The HVAC system, on model 579 and 567 vehicles manufactured since 1/20/2012 may have inadequate temperature control. 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.
02-1582020-09-03. Service bulletin. EQUIPMENT; STRUCTURE; EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM:12V/24V/48V BATTERY. Fix as Fail: Peterbilt has determined that certain model 348, 365, 367, 382, 384, 386, 388, 389, 567, 579, and 587 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.
32-0152020-07-03. Service bulletin. ELECTRICAL SYSTEM. Information Only: This bulletin provides dealers with a battery warranty quick reference guide to ensure the appropriate tests for battery warranty are performed in order to prevent battery warranty claims filed with incorrect or incomplete information.
20PBA2020-05-06. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ELECTRICAL SYSTEM. "Safety Recall: NHTSA recall number is 20V130. A defect, which relates to motor vehicle safety, may exist in certain Model 365, 389, 567, and 579 vehicles manufactured between April 18, 2014 and March 09, 2020 with a left-hand under hood jumper start terminal. Jumper terminal battery cables may be too long, or eligible for improved routing. Battery cables that are too long may chafe against the left front suspension leaf spring, which could cause a short circuit, fire under the hood, or increased risk of crash. "
20PBA2020-04-03. Service bulletin. ELECTRICAL SYSTEM. Safety Recall Interim Bulletin: Peterbilt has decided that a defect, which relates to motor vehicle safety, may exist in certain Model 365, 389, 567, and 579 vehicles manufactured between April 18, 2014 and September 30, 2019 with a left-hand under hood jumper start terminal. Your vehicle may have jumper terminal battery cables that are too long, or are eligible for improved routing. Battery cables that are too long may chafe against the left front suspension leaf spring, which could cause a short circuit, fire under the hood, or increased risk of crash.
34-0862020-04-03. Service bulletin. ELECTRICAL SYSTEM. Fix as Fail: Peterbilt has determined in model 567 and 579 vehicles built after 2011, the door harnesses may fail due to repeated door open and close cycles. Resolution is to replace the door harness with a more robust designed harness if a failure is experienced.
32-0132020-02-05. Service bulletin. ELECTRICAL SYSTEM. Information Only: The AutoStart System Test does not recognize the hood opening and closing when running the test on a model 579 or 567 chassis equipped with a VECU software version 9.8 and 9.9. The issue will be fixed on a future VECU software update. This bulletin will be updated when the resolution is available.
03-0712020-01-04. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. Information Only - Vehicles built with NAMUX software from 2013 to present may experience accuracy issues with the tachometer. The issue can be temporarily resolved using any one of the included procedures.
01-0782020-01-04. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. Fix as Fail: Peterbilt has determined that certain models 567 and 579 vehicles built after January 01, 2013 with an Espar fuel fire heater and SmartAir may have an auto On/Off malfunction at lower temperatures. User may experience lack of heat function on SmartAir if the set temperature is < 76 °F. Resolution is to install a jumper harness.

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