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Service bulletins for the 2020 Chevrolet Blazer

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.

854 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
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.
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.
24-NA-0682024-09-25. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides a procedure to test and replace the battery distribution fuse block if found the cause of the DTC and electric coolant pump inoperative.
23-NA-1642024-09-12. Service bulletin. STRUCTURE:BODY; ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Vehicle Will Lock and Unlock (Active Functions Work) but Will Not Crank or Start (Loss of Passive Functions Do Not Work)
23-NA-1632024-09-11. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This service bulletin provides repair information to correct a customer concern of No Crank, No Start, Quick Start/Stall, No FOB Detected, Key FOBs Inoperative, B3924 00, B3925 00, B3926 00, B3927 00, B3928 00 Set.
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.
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.
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.
12-01-37-001G2024-08-13. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This service bulletin provides information to dealership personnel on a new refrigerant (R1234yf) for A/C service.
18-NA-1252024-06-28. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This service bulletin provides information for engine oil life monitor operation calculation.
24-NA-0982024-06-25. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491, E4492, or E6961 and resolution information.
21-NA-2762024-06-24. Service bulletin. POWER TRAIN; ENGINE; ELECTRICAL SYSTEM. This service bulletin provides a procedure to correct a customer concern of Starter Not Cranking Engine, Starter Inoperative, Grinding Noise When Starting.
21-NA-0682024-06-22. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information requirements applicable to key fob replacement under the New Vehicle Limited Warranty or under a Replacement Parts Warranty on 2017-2022 and newer model year vehicles with RPO ATH and AVJ.
23-NA-0642024-06-10. 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.
18-NA-1252024-06-08. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This service bulletin provides information for engine oil life monitor operation calculation.
22-NA-2442024-05-30. Warranty extension. ELECTRICAL SYSTEM; EXTERIOR LIGHTING; STRUCTURE:BODY; UNKNOWN OR OTHER; SERVICE BRAKES. This service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
23-NA-0642024-05-16. 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.
13-08-116-001J2024-05-16. 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.
23-NA-1252024-05-16. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on Over The Air (OTA) and In Market Enhancement (IME) FAQs.
18-NA-2792024-05-15. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on the process to disable and enable passive unlocking.
23-NA-0642024-05-02. 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.
20-NA-1322024-04-23. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.

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