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Service bulletins for the 2021 Mack LR

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.

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

By type

By component

By trouble code

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

Bulletins, newest first
KC-21122022-07-05. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN; ENGINE AND ENGINE COOLING. Programming Failure - Chassis With Cummins Engine And An Allison Transmission
KC-3992022-07-05. Service bulletin. ELECTRICAL SYSTEM. Vehicle Overspeed Warning Comes Active At A Lower Speed Than Expected; Vehicle Overspeed Warning In Driver Information Display (DID) - Model Year 2018 And Newer With New Style Instrument Cluster.
KC-21722022-06-07. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. No Start Condition After Over The Air Programing - VECU5 No Start "Safe State"
KC-21692022-06-07. Service bulletin. ELECTRICAL SYSTEM. Low Voltage Disconnect (LVD), Function Description
KC-6992022-06-07. Service bulletin. ELECTRICAL SYSTEM. Mack Chassis - Bendix Vendor Configuration Program ( VCP ) Software Download Information
KC-4022022-02-04. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; ELECTRICAL SYSTEM. Volvo Chassis - Diagnostic Trouble Code (DTC) SA 0 FMI 0 or SPN 0 FMI 0 Present On Fault Code Readout - US10 And Newer Emissions, Model Year 2011 And Newer
KC-3542022-02-04. Service bulletin. ELECTRICAL SYSTEM; ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. Volvo Chassis - Certain Volvo Trucks Built After January 11, 2016 May Experience an Issue with the Instrument Cluster Display
KC-20432022-01-08. Service bulletin. ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; ELECTRICAL SYSTEM:SOFTWARE. Engine Control Module (EMS) Software (MSW) Information - Improvement List, November 2021 - US21+OBD2020 Emissions
SNM21-0062021-11-04. Service bulletin. COMMUNICATION:MANUFACTURER TELEMATICS; UNKNOWN OR OTHER; ELECTRICAL SYSTEM:SOFTWARE. Remote Software Downloads
KC-3282021-10-01. Service bulletin. ELECTRICAL SYSTEM. Diagnostic Trouble Codes (DTC) P208064, P208464, P242B64 and P246F64 Lighting The Malfunction Indicator Lamp (MIL) - US17+OBD19 And Newer Emissions, Model Years 2020 and Newer
S75572021-03-03. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. VECU Active code and no MIL Lights
K011572832020-04-03. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:BELTS AND ASSOCIATED PULLEYS; ELECTRICAL SYSTEM. Front Accessory Drive Noise, Alternator Belt Wear, Alternator Belt Tensioner Failure - Model Year 2017 And Newer

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