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Service bulletins for the 2021 GMC Sierra

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.

1649 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

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

Bulletins, newest first
18-NA-1032023-09-01. Service bulletin. ELECTRICAL SYSTEM; FUEL SYSTEM, DIESEL. This service bulletin provides service information for customer concerns of an in-tank fuel pump whining noise, engine hard to start and/or stalls and Malfunction Indicator Lamp (MIL) is illuminated that may be caused by gelling of fuel in cold temperatures.
20-NA-0902023-08-03. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
09-06-04-026X2023-08-03. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
23-NA-0272023-07-26. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to test and replace the high-pressure fuel injector electrical connectors if found the cause of the MIL.
22-NA-1832023-07-26. Service bulletin. TIRES; ELECTRICAL SYSTEM; WHEELS. This service bulletin advises the technician of a different tire/rim option that can be used to correct a customer concern of poor ride quality at highway speeds.
23-NA-1252023-07-25. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides information for dealers/technicians on Over the Air (OTA) and In Market Enhancement (IME) FAQs.
23-NA-0552023-07-25. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides information on the EL-52800 Diagnostic & Charge Battery Station (DCBS) – FAQs.
07-08-42-006S2023-07-25. Service bulletin. EXTERIOR LIGHTING; ELECTRICAL SYSTEM. This service bulletin provides technicians with information on available BCM calibrations to restore bulb outage detection on vehicles produced by a second stage manufacturer (Upfitter), and/or turn signals flash fast after factory box removed.
PIT60312023-07-17. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates an issue where an aftermarket autostop device is causing a dead battery.
23-NA-1122023-07-14. Service bulletin. STRUCTURE:BODY:TAILGATE; STRUCTURE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct the condition of Inadvertent/Unwanted Tail Gate Opening.
23-NA-0642023-07-14. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.
23-NA-0422023-07-14. Service bulletin. BACK OVER PREVENTION:SOFTWARE; EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides repair information to update radio software to correct customer concerns of Software related issues.
21-NA-0052023-07-14. Service bulletin. ELECTRICAL SYSTEM; AIR BAGS. This technical bulletin provides a procedure to replace the air bag and air bag harness to correct a condition of Airbag Malfunction Warning and Airbag Malfunction Indicator Illuminated with DTC B0001-1B due to corrosion.
13-08-116-001I2023-07-13. Service bulletin. ELECTRICAL SYSTEM. The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
21-NA-0612023-07-11. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM. This service bulletin provides information for dealers on Using EL-52545 When Diagnosing PEPs Transmitter Key Fobs.
23-NA-0622023-06-19. Service bulletin. EQUIPMENT; BACK OVER PREVENTION: SENSING SYSTEM: CAMERA; ELECTRICAL SYSTEM. This service bulletin provides repair information to correct a customer concern of Rear View Camera Issues - DTCs B395A, B395B, B395C, B101E, B101D.
PIT5509K2023-06-13. Service bulletin. AIR BAGS; ELECTRICAL SYSTEM; TRAILER HITCHES. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System? message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
PIT3665M2023-06-13. Service bulletin. ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL. This Preliminary Information communication advises the technician that the Hydro-Boost is not serviceable and will need to be replaced if the brake pedal moves or applies on its own at a full turn.
PIC5650K2023-06-13. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:IGNITION. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
22-NA-1502023-06-05. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to program the Reductant Control Module and Setup and Perform the Reductant Fluid Tank Level Reset.
PIT5509J2023-05-15. Service bulletin. ELECTRICAL SYSTEM; TRAILER HITCHES. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System? message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
22-NA-2102023-05-10. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to locate and repair a broken ground stud at the NOx converter.
23-NA-0272023-05-06. Service bulletin. ELECTRICAL SYSTEM; FUEL SYSTEM, DIESEL. This technical bulletin provides a procedure to test and replace the high-pressure fuel injector electrical connectors if found the cause of the MIL.
22-NA-2472023-05-04. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM. This service bulletin provides information to dealership personnel that after performing a brake inspection, brake pad replacement, or any other repair that requires the caliper piston to be reseated may be causing DTC C05B0 to falsely set for eBoost applications.
22-NA-0852023-05-04. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides radio software version 135120 (IOR) update procedures to correct customer concerns of software related issues.

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