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Service bulletins for the 2020 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.

1990 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
PIT5386K2024-12-20. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about vehicles that are found to have a back-up alarm inoperative during the Pre-Delivery Inspection. On trucks equipped with the Back Up Alarm (RPO 8S3), the alarm will be intentionally left disconnected from the assembly plant. Technician will reroute the harness and plug it in.
22-NA-2382024-12-19. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This service bulletin provides diagnostic/repair information to correct a customer concern of Cellphone not Charging or USB Receptacle Inoperative.
PIT5962B2024-12-12. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary information communicates a GM part number for reflective high temperature heat or insulating tape when repairing wiring harnesses.
PIT5860B2024-12-05. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates and issue with a no crank, Key Learn Pending or Ready For FOB 3 Message, Unable To Exit RVS With Push To Start Button, Symptoms Of A Dead Battery and has dealership inspect to see if the vehicle is falsely entering the manual transmitter programming and if so to replace the drivers power window switch.
24-NA-2392024-12-05. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This informational bulletin provides a guide on how to diagnose and test for vibrations utilizing the PicoScope.
PIT5868C2024-12-04. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary information communicates an issues will low or poor heater performance on the drivers side. Dealers are to inspect the HVAC temperature door linkage and if ok replace the heater core.
24-NA-2292024-12-02. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides a procedure on how to check for a battery drain utilizing the Picoscope and how to measure the load on the system that may be causing a drain.
20-NA-1322024-11-09. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.
23-NA-0642024-11-05. Service bulletin. ELECTRICAL SYSTEM. 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.
PIT5698E2024-10-25. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates additional information on how a LIN bus operates and diagnostic tips when working on a LIN bus.
PIP4723J2024-10-25. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
23-NA-2012024-10-24. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM; STEERING. This service bulletin advises the technician of a possible loose ground that may be causing customer concerns of Loss of Steering Assist and/or Loss of Brake Assist and Malfunction Indicator Lamp (MIL) Illuminated.
21-NA-1662024-10-24. Service bulletin. ELECTRICAL SYSTEM; STEERING. This informational bulletin provides information on the turn signal stalk not cancelling and/or mis cancelling.
PIT5569C2024-10-18. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates direction and examples when diagnosing multiple DTCs, one of which includes U**** Byte 71 DTC.
21-NA-1492024-10-09. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides repair information for Engine Wire Harness Chafing to correct customer concerns of IPC Gauges Sweep, IPC Warning Message, SES/Check Engine/MIL, No Start/ No Crank, Runs Rough, Stalls, Reduced Engine Power, Various DTCs.
23-NA-0442024-09-11. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides information on AGM batteries that require less frequent charging in storage.
PIC5650L2024-09-06. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. 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.
PIT61982024-09-06. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary information communicates a diagnostic tip for an SES MIL at startup with DTC U0100. Dealer are to test the accessory wake up circuit to the ECM for power.
09-06-04-026Y2024-09-05. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
20-NA-0902024-08-28. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
General Communication2024-08-26. Service campaign. ELECTRICAL SYSTEM. Vehicle Wide Programming (VWP) is a new process to update software on GM Vehicles. It provides the ability via a single selection within Techline Connect to first identify which modules need updating and then proceed to updating affected modules (with some exceptions). The updating of modules is completed in parallel instead of the technician needing to update one module at a time. This allows a more streamlined approach for dealers and customers.
PIT5481J2024-08-16. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician with additional information on the functionality of Lane Keep Assist. Starting with 2016 model year Lane Keep Assist Regular Production Option Code (UHX) replaced Lane Departure Warning Regular Production Option Code (UFL). Lane Keep Assist is designed to assist the driver in keeping the vehicle from drifting out of a driving lane that has clearly identified markings. The electric power steering provides a gentle steering correction if a lane marking has been crossed and the driver has not actively responded.
18-NA-2792024-08-14. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on the process to disable and enable passive unlocking.
PIT5832P2024-08-14. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This Preliminary information communicates a diagnostic tip on how to resolve a issue if the serial data authentication configuration did not complete correctly.
PIT6134A2024-08-13. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates an issue with premature brake pad life and engineering is working on release new pad lining material.

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