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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

Bulletins, newest first
21-NA-1242023-01-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set.
18-NA-0732023-01-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
16-NA-3382023-01-05. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
22-NA-2472022-12-24. Service bulletin. SERVICE BRAKES, HYDRAULIC. 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-2442022-12-21. Service bulletin. EQUIPMENT. This service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
22-NA-2402022-12-15. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin advises the tech to validate if oil is leaking into the cooling system and to test and verify were to leak is coming from before replacing all the parts that wouldn't apply to the repair.
PIT3271N2022-12-12. Service bulletin. WHEELS; TIRES. This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.
PIT5662G2022-12-12. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates information to diagnose DTC C056D or C056E.
PIT5481H2022-12-12. Service bulletin. STEERING; LANE DEPARTURE. 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.
22-NA-2382022-12-07. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides diagnostic/repair information to correct a customer concern of Cellphone not Charging or USB Receptacle Inoperative.
PIE0720A2022-12-07. Service bulletin. POWER TRAIN. This engineering information (EI) closure ends the need to gather further information from technicians in regards to Vehicle Will Not Move When in Drive, Neutral and/or Reverse and DTCs P0746, P0747 Set.
19-NA-0782022-12-07. Service bulletin. WHEELS. This warranty administration bulletin provide policy information on tires are not meeting tread depth expectations, or wearing out (reaching 2/32)) too quickly.
20-NA-1382022-12-06. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
22-NA-0742022-12-03. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.
PIT5843A2022-11-21. Service bulletin. LATCHES/LOCKS/LINKAGES:DOORS:LOCK. This Preliminary information communicates that a vehicle may come to the dealer with concerns of various warning messages, possibly the door locks cycling, passive entry inoperative or other concerns. The technician is instructed to inspect G401 for loose or missing terminals and to inspect G405.
PIT5847G2022-11-21. Service bulletin. POWER TRAIN. This Preliminary information communicates that a vehicle may come into the dealer with various concerns which may include a service engine light or various warning messages on the DIC. The technician is instructed to inspect a wiring harness for chaffing on a bracket which is located beneath the battery tray, at a transmission stud and at the transmission oil cooler line bracket. If damage to the harness is found the technician is instructed to repair the damaged wiring and secure the harness away from the bracket so that future damage to the harness will be eliminated.
22-NA-0852022-11-09. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides radio software version 135120 (IOR) update procedures to correct customer concerns of software related issues.
17-NA-2712022-11-03. Service bulletin. WHEELS; SERVICE BRAKES, HYDRAULIC. This bulletin provides a procedure to clean the back side of the rims and rotors and to correct the customers concern of wheel clicking.
22-NA-2052022-11-02. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information on Module Harvesting.
22-NA-0852022-11-02. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides radio software version 135120 (IOR) update procedures to correct customer concerns of software related issues.
PIE07202022-10-28. Service bulletin. POWER TRAIN. This engineering information (EI) is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to Vehicle Will Not Move When in Drive, Neutral and/or Reverse and DTCs P0746, P0747 Set.
99-00-89-019X2022-10-28. Service bulletin. STRUCTURE. This Warranty Administration bulletin provides information on the Global Warranty Management (GWM) Warranty Parts Center (WPC) Parts Return Program.
10-00-89-006I2022-10-28. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This service bulletin provides information for dealers on how to submit a product information report (PIR) (Canada Only).
PIC5453D2022-10-17. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician that General Motors and General Motors of Canada Company do not support cross border sales. The General Motors of Canada Customer Care Centre is the sole authorized provider of a certification confirmation letter which helps our customers identify if their vehicles meets the required USA regulatory standards necessary for importation into the USA.
PIT5698C2022-10-17. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates additional information on how a LIN bus operates and diagnostic tips when working on a LIN bus.

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