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.
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Only bulletins with type: Service campaign are shown. Show all
| N252508350 | 2025-10-21. Service campaign. ENGINE. Certain vehicles listed above, may have a condition that could cause the engine coolant thermostat to open at a lower temperature than intended. If this condition were to occur, the Malfunction Indicator Lamp (Check Engine Light) will illuminate and a diagnostic trouble code will set. Additionally in some cases, the engine cooling fans may run after the engine is switched off. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after October 21, 2025, are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair orders prior to October 21, 2025, must be submitted to the Service Contract provider. Vehicle owners or lessees who paid for repairs referenced in this Special Coverage (“Customers”) are eligible for reimbursement of their reasonable and customary expenses in accordance with the procedures specified below. The conditional right to reimbursement is provided by GM solely in the interest of customer satisfaction and is personal to Customers. Customers may not assign and GM does not consent to any assignment of any Customer’s right to submit reimbursement claims, or to receive reimbursement, or any other rights granted by this Special Coverage to any third party, including but not limited to service contract providers, and this Special Coverage is not intended to and does not confer any third party beneficiary, subrogation or contribution rights, or any other rights to reimbursement, against GM, whether in law, equity or otherwise, on any third parties. Dealers are to replace the engine coolant thermostat as necessary. The repairs will be made at no charge to the customer. |
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| N252494770-01 | 2025-06-20. Service campaign. UNKNOWN OR OTHER. Amendments to the Song-Beverly Act (SBA) California warranty law provides vehicle owners with an opportunity to submit a written notice to GM before filing a lawsuit seeking a vehicle repurchase. If such a notice is not provided to GM, then the vehicle owner is prevented from seeking civil penalties in litigation. Vehicle owners of the affected vehicles will be mailed an owner’s manual and warranty insert containing this information in English and Spanish. |
| N252494770 | 2025-06-17. Service campaign. UNKNOWN OR OTHER. Amendments to the Song-Beverly Act (SBA) California warranty law provides vehicle owners with an opportunity to submit a written notice to GM before filing a lawsuit seeking a vehicle repurchase. If such a notice is not provided to GM, then the vehicle owner is prevented from seeking civil penalties in litigation. Vehicle owners of the applicable vehicles will be mailed an owner’s manual and warranty insert containing this information in English and Spanish. |
| General Communication | 2024-08-26. 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. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.