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Service bulletins for the 2021 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.

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

By type

By component

By trouble code

By topic

Bulletins, newest first
19-NA-0442024-02-21. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; FUEL SYSTEM, GASOLINE. This service bulletin provides information on the cold start control system in DI engines to reduce cold start emissions and improve fuel economy.
16-NA-2222024-02-21. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides information on Engine Concerns that could result from lack of scheduled maintenance, improper service or aftermarket calibrations.
16-NA-3382024-02-17. 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.
23-NA-1892024-02-14. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin assists technicians in setting up PicoScope hardware/software to monitor CAN bus traffic (voltage patterns) to aid Technical Assistance (TAC) and Field Service Engineers (FSEs) in diagnosing electrical issues present on network communication circuits.
23-NA-0552024-02-14. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides information on the EL-52800 Diagnostic & Charge Battery Station (DCBS) – FAQs.
23-NA-2142024-02-14. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides Information on Purge Pump Part Replacement and Purge pump Part Number Interchangeability.
23-NA-0722024-02-14. Service bulletin. POWER TRAIN. This service bulletin provides a procedure to correct a customer concern of Shudders or Shakes at Low Speeds.
PI0281K2024-02-14. Service bulletin. STRUCTURE. This preliminary informational (PI) bulletin provides information to dealership personnel which may be helpful when addressing underbody component corrosion with customers.
PIT6097C2024-02-12. Service bulletin. EQUIPMENT:ELECTRICAL. This Preliminary information communicates an issue where the vehicles wireless charger no longer works with certain ISO updates on Apple 15 phones and advises customer to update their phone to the lastest ISO update.
PIT61162024-02-12. Service bulletin. STRUCTURE:BODY:HATCHBACK/LIFTGATE. This Preliminary information communicates information to help diagnose inoperative rear liftgate logo.
PIP5601B2024-02-12. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician about vibration complaints that are one of the most challenging complaints to accurately diagnose and repair. Technician will need to use Pico Oscilloscope Diagnostic Kit to effectively diagnosis vehicles. Technician should drive the vehicle will using the Pico Oscilloscope to record data. After the data is recorded it should be reviewed to determine the root cause of the concern. If a repair attempt made the concern better but not eliminated or had no affect at all, and are requesting assistance from General Motors Technical Assistance Center record another Pico file and save it to the computer. After the new Pico Oscilloscope data has been saved email the data to General Motors Technical Assistance Center in the subject line include ?Vibration? ?Business Associate Code? and the last 8 of the Vehicle Identification Number.
PIT6084A2024-02-12. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT. This PI states that a vehicle may exhibit a concern of the cross traffic alert indicators not displaying on the radio screen. While this is a customer dissatisfier, it does not pose a safety concern due to the fact that the customer will still be alerted to an approaching vehicle by the seat vibration. Dealers are advised that engineering is working on a resolution and it will be available by the end of 2023.
PIP5824C2024-02-12. Service bulletin. FUEL SYSTEM, GASOLINE. This Preliminary information communicates a possible issue with the active fuel management rockers causing a misfire and the correction for this concern.
PIP5841D2024-02-12. Service bulletin. POWER TRAIN. This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set.
18-NA-0992024-02-02. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This bulletin provides information for use on a Product Assistance Claim (PAC), which is formerly known as a Product Allegation Resolution (PAR) claim.
PI1394B2024-02-02. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This PI bulletin advises the technician on the proper way to install the pistons in an engine.
PI0592I2024-02-02. Service bulletin. ELECTRICAL SYSTEM. This preliminary information (PI) provides information om Service Programming System (SPS) Error Codes (E4398, E4399, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491 or E6961).
PIT5684A2024-01-29. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates information for terminal concerns at X203
PIT5673A2024-01-29. Service bulletin. EXTERIOR LIGHTING; EXTERIOR LIGHTING:HEADLIGHTS. This Preliminary information communicates information for Intellibeam headlamp inoperative and to inspect the low speed data line.
PIT5074P2024-01-29. Service bulletin. EQUIPMENT. This Preliminary Information communication provides information to the technician about the use of J-35616-64B terminal test probe, replacement terminals, and terminated leads. The J-35616-64B is the latest test probe released for checking tension or probing the .64 series terminals. The test probe terminal has been released in the terminal repair kit (J-38125-620H) located in Lear Tray 7 part number 963716-2. There are 5 terminated leads in a package part number is 13505346, which can be ordered through your normal General Motors Customer Care and Aftersales parts channel.
PIT5962A2024-01-29. Service bulletin. ELECTRICAL SYSTEM:HAND HEATER:WIRING HARNESS; UNKNOWN OR OTHER. This Preliminary information communicates a GM part number for reflective high temperature heat or insulating tape when repairing wiring harnesses.
PIT6097B2024-01-29. Service bulletin. EQUIPMENT:ELECTRICAL; EQUIPMENT:ELECTRICAL:WIRELESS CHARGER/CRADLE. This Preliminary information communicates an issue where the vehicles wireless charger no longer works with the latest ISO update on Apple 15 phones.
PIT6097A2024-01-29. Service bulletin. EQUIPMENT:ELECTRICAL:WIRELESS CHARGER/CRADLE. This Preliminary information communicates an issue where the vehicles wireless charger no longer works with the lastest ISO update on Apple 15 phones.
PIT60972024-01-29. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT:SOFTWARE; EQUIPMENT:ELECTRICAL:INFOTAINMENT. This Preliminary information communicates an issue where the vehicles wireless charger no longer works with the lastest ISO update on Apple 15 phones.
22-NA-2402024-01-19. 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.

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