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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: Equipment and accessories are shown. Show all

Bulletins, newest first
20NA1362021-12-27. Service bulletin. EQUIPMENT; POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
19NA1042021-12-27. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT. This service bulletin provides information for dealers/technicians and customers on steam/vapor coming from the front grille or radiator area.
PIC6438B2021-09-13. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This Preliminary information communicates a condition where the Video Processing Control Module is not able to be programmed to the vehicle. This PI offeres a couple workarounds while Engineering evaluates the concern.
PIT3099U2021-09-13. Service bulletin. EQUIPMENT. This Preliminary Information communication provides information to the technician about installing General Motors Accessory parts/kits. Technicians should refer to Service Information for information regarding most accessories. Technicians may also contact PARTECH and/or the Techline Customer Support Center for additional support.
PIT58452021-09-13. Service bulletin. ELECTRICAL SYSTEM; VEHICLE SPEED CONTROL; EQUIPMENT. This Preliminary information communicates information to diagnose adaptive cruse with DTC U0422 in the EBCM.
PIP5632E2021-09-13. Service bulletin. EQUIPMENT:ELECTRICAL:ACCESSORY GENERATOR:CONTROLS. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
PIP58142021-09-13. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ELECTRICAL SYSTEM. This Preliminary information communicates that there some service parts released to dealers missing software.
990420002L2021-08-09. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
110089002E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This service bulletin provides information on GM Accessories ? Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
080730035E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
010842001N2021-08-09. Service bulletin. EXTERIOR LIGHTING; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. This service bulletin provides information for dealers/technicians on Exterior Lamp Condensation and Water Leaks and Replacement Guidelines.
21NA1522021-08-09. Service bulletin. VISIBILITY:GLASS, SIDE/REAR; EQUIPMENT. This service bulletin provides information for dealers/technicians on glass ultraviolet (UV) Ray protection and tint percentage.
21NA1472021-08-09. Service bulletin. ELECTRICAL SYSTEM:IGNITION:COIL:SPARK PLUGS; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE AND ENGINE COOLING. This service bulletin provides a repair procedure to correct a customer concern of Coolant and/or Oil Leak, Malfunction Indicator Lamp (MIL) Illuminated?.
21NA1452021-08-09. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT. This service bulletin provides U157 software update information to correct customer concerns of radio Software related issues.
100089006H2021-08-09. Service bulletin. EQUIPMENT. This service bulletin provides information for dealers on how to submit a product information report (PIR) (Canada Only).
070089037Q2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
070089037P2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
20NA1592021-07-19. Service bulletin. EQUIPMENT. This Warranty Administration bulletin is for information on General Motors New Vehicle Tire Warranty Program (U.S. Dealers Only).
19NA0762021-07-19. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides repair information to correct a customer concern of Blue or Black Screen and Service Rear Vision System Message on Radio Display Shifting into Reverse.
18NA3062021-07-19. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA).
18NA3062021-07-06. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA).
PIT5839A2021-06-14. Service bulletin. EQUIPMENT:APPLIANCE:TV/RADIO/SPEAKERS; EQUIPMENT. This Preliminary information communicates to GM dealers that the above mentioned concern is software related and that General Motors is working on a solution.
070089036J2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information on Enhancing Field Product Reports with Digital Pictures.
020089002T2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information for dealers/technicians on When and How to Submit a Field Product Report (FPR) (U.S. Dealers Only).
21NA1032021-05-24. Service bulletin. EQUIPMENT. This service bulletin provides information regarding Witness Marks from Panel Adjustments Made During Manufacturing and that it is considered a normal condition.

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