Service bulletin 21-NA-135
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.
| Type | Service bulletin |
|---|---|
| NHTSA id | 10245559 |
| Published by NHTSA | 2023-11-29 |
| Manufacturer's number | 21-NA-135 |
| Manufacturer's date | 2023-11-16 |
| NHTSA component | ENGINE AND ENGINE COOLING; EQUIPMENT; EXTERIOR LIGHTING; ELECTRICAL SYSTEM |
NHTSA's summary
This service bulletin provides information to inform dealership personnel about Law Enforcement and Government vehicles that request to disable or enable content.
The document
The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.
Components
Electrical system, Engine, Equipment and accessories, Lighting
| BUICK CASCADA | 2019 |
|---|---|
| BUICK ENCLAVE | 2019, 2020, 2021, 2022, 2023, 2024 |
| BUICK ENCORE | 2019, 2020, 2021, 2022 |
| BUICK ENCORE | 2023 to 2024 |
| BUICK ENCORE GX | 2020, 2021, 2022, 2023, 2024 |
| BUICK ENVISION | 2019, 2020, 2021, 2022, 2023, 2024 |
| BUICK ENVISTA | 2024 |
| BUICK LACROSSE | 2019 |
| BUICK LACROSSE | 2020 |
| BUICK REGAL | 2019, 2020 |
| BUICK REGAL TOURX | 2020 |
| CADILLAC ATS | 2019 |
| CADILLAC CT4 | 2020, 2021, 2022, 2023, 2024 |
| CADILLAC CT5 | 2020, 2021, 2022, 2023, 2024 |
| CADILLAC CT6 | 2019, 2020 |
| CADILLAC CT6 | 2021 |
| CADILLAC CTS | 2019 |
| CADILLAC ESCALADE | 2019, 2020, 2021, 2022, 2023, 2024 |
| CADILLAC ESCALADE ESV | 2019, 2020, 2021, 2022, 2023 |
| CADILLAC ESCALADE NA | 2021 (the catalog's model; the bulletin names a series or trim of it) |
| CADILLAC LYRIQ | 2023, 2024 |
| CADILLAC XT4 | 2019, 2020, 2021, 2022, 2023, 2024 |
| CADILLAC XT5 | 2019, 2020, 2021, 2022, 2023, 2024 |
| CADILLAC XT6 | 2020, 2021, 2022, 2023, 2024 |
| CADILLAC XTS | 2019 |
| CADILLAC XTS | 2020 |
| CADILLAC redundant LYRIQ | 2024 |
| CHEVROLET 6500 | 2019 |
| CHEVROLET BLAZER | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET BLAZER EV | 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET BOLT EUV | 2022, 2023 |
| CHEVROLET BOLT EV | 2019, 2020, 2021, 2022, 2023 |
| CHEVROLET BOLT EV | 2024 |
| CHEVROLET CAMARO | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET COLORADO | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET CORVETTE | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET CRUZE | 2019 |
| CHEVROLET EQUINOX | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET EQUINOX EV | 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET EXPRESS | 2019, 2020, 2021 |
| CHEVROLET EXPRESS 2500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET EXPRESS 3500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET EXPRESS CUTAWAY VAN | 2019, 2020, 2021, 2022, 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET IMPALA | 2019, 2020 |
| CHEVROLET MALIBU | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET MALIBU HYBRID | 2019 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 1500 | 2019, 2020, 2021 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 1500 | 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 2500 | 2019, 2020, 2021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 3500 | 2019, 2020, 2021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 4500 | 2019, 2020, 2021, 2022, 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 5500 | 2019, 2020, 2021 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 5500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 6500 | 2019 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 6500 | 2021, 2022, 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO EV | 2024 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SONIC | 2019, 2020 |
| CHEVROLET SPARK | 2019, 2020, 2021, 2022 |
| CHEVROLET SUBURBAN | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET SUBURBAN 1500 | 2021, 2022, 2023 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET TAHOE | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET TRAILBLAZER | 2019 to 2020 |
| CHEVROLET TRAILBLAZER | 2021, 2022, 2023, 2024 |
| CHEVROLET TRAVERSE | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET TRAX | 2019, 2020, 2021, 2022, 2023, 2024 |
| CHEVROLET VOLT | 2019 |
| CHEVROLET duplicate SILVERADO 5500 | 2019 |
| GMC 3500HD | 2024 |
| GMC ACADIA | 2019, 2020, 2021, 2022, 2023, 2024 |
| GMC CANYON | 2019, 2020, 2021, 2022, 2023, 2024 |
| GMC HUMMER EV PICKUP | 2022, 2023, 2024 |
| GMC HUMMER EV SUV | 2024 |
| GMC SAVANA | 2019, 2020, 2021, 2022, 2023, 2024 |
| GMC SAVANA 2500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SAVANA 3500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 1500 | 2019, 2020, 2021 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 1500 | 2024 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 2500 | 2019, 2020, 2021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 3500 | 2019, 2020, 2021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA DENALI | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
| GMC TERRAIN | 2019, 2020, 2021, 2022, 2023, 2024 |
| GMC TERRAIN NA | 2022 (the catalog's model; the bulletin names a series or trim of it) |
| GMC YUKON | 2019, 2020, 2021, 2022, 2023 |
| GMC YUKON DENALI | 2019 (the catalog's model; the bulletin names a series or trim of it) |
| GMC YUKON XL | 2019, 2020, 2021, 2022, 2023, 2024 |
| GMC YUKON XL 1500 | 2023 (the catalog's model; the bulletin names a series or trim of it) |
Listing a model year does not mean every vehicle of it is concerned: the document says which.
| 25V876000 | 2025-12-17. EQUIPMENT ADAPTIVE/MOBILITY:WHEELCHAIR RESTRAINTS/SECUREMENT:LATCH/ANCHOR: |
|---|---|
| 2025225 | 2025-04-24. Engine |
| 25V274000 | 2025-04-24. ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL |
| 24V755000 | 2024-10-10. EXTERIOR LIGHTING:LIGHTING CONTROL MODULE |
| 2024519 | 2024-09-12. Lights And Instruments |
| 2024518 | 2024-09-12. Lights And Instruments |
| 24V673000 | 2024-09-12. EXTERIOR LIGHTING:HEADLIGHTS |
| 24V575000 | 2024-08-01. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL |
| 24V320000 | 2024-05-09. ELECTRICAL SYSTEM:PROPULSION SYSTEM; ELECTRICAL SYSTEM:WIRING |
| 24V133000 | 2024-02-22. ELECTRICAL SYSTEM:ADAS:DRIVER MONITORING:CAMERA/SENSOR; FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING |
A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.
| N262570770-03 | 2026-10-16. Service campaign. Certain vehicles may have a condition in which the thermal break tabs induce stress into the radiator causing a coolant leak. Dealers are to cut the thermal break tabs on the radiator. |
|---|---|
| N262576260 | 2026-10-15. Service campaign. General Motors has decided to conduct a Voluntary Emission Recall. Certain vehicles may have a condition that could cause a small exhaust leak at the catalytic converter inlet. Dealers are to replace the catalytic converter inlet clamp and to inspect the catalytic converter – replacing it if damage is observed. The repairs will be made at no charge to the customer. |
| N262570770-02 | 2026-09-25. Service campaign. Certain vehicles may have a condition in which the thermal break tabs induce stress into the radiator causing a coolant leak. Dealers are to cut the thermal break tabs on the radiator. |
| N262570770-01 | 2026-09-18. Service campaign. Certain vehicles may have a condition in which the thermal break tabs induce stress into the radiator causing a coolant leak. Dealers are to cut the thermal break tabs on the radiator. |
| N262570770 | 2026-09-15. Service campaign. Certain vehicles may have a condition in which the thermal break tabs induce stress into the radiator causing a coolant leak. Dealers are to cut the thermal break tabs on the radiator. |
| N242484750-02 | 2026-09-01. Warranty extension. Special Coverage. Certain 2022 model year Buick Encore GX and Chevrolet Trailblazer vehicles, equipped with a 1.2L engine, may have a condition that could cause the turbocharger to fail. If this condition occurs, the Malfunction Indicator Lamp (Check Engine Light) will illuminate, and a diagnostic trouble code will set. Additionally, a message may be displayed indicating the vehicle’s available engine power is reduced. 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 January 14, 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 January 14, 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 turbocharger as necessary. The repairs will be made at no charge to the customer. |
| N252541251 | 2026-07-15. Service campaign. Certain vehicles listed above may have a condition in which drivers may not be notified of a rear turn-signal lamp failure. GM will update software calibrations in the vehicle’s exterior lighting control module. For vehicles that are capable of receiving software changes using wireless over-the-air (OTA) technology, owners who have accepted applicable terms and conditions will have the opportunity to accept these software changes via OTA without having to bring their vehicle to a dealership. Alternatively, all owners may have the updates performed at a GM dealer. |
| N262546590-01 | 2026-07-15. Service campaign. Certain vehicles listed above, may have a condition where coolant leaks from the radiator hose quick connect at the radiator inlet. This special coverage covers the condition described above for a period of 5 years or 60,000 miles (100,000 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 July 14, 2026, 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 July 14, 2026, 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 remove the inlet hose and replace the seal. The repairs will be made at no charge to the customer. |
| N242468490-02 | 2026-05-28. Service campaign. Certain vehicles may have missing cavity plugs from the rear chassis harness electrical connector. Dealers are to inspect the rear chassis harness and replace missing harness plugs as necessary. |
| N262552620 | 2026-05-11. Service campaign. Certain vehicles may have a condition that could cause the cylinder 2 glow plug to fail. If this failure occurs, the Malfunction Indicator Light (Check Engine Light) will illuminate and a diagnostic trouble code will set. 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 May 11, 2026, 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 May 11, 2026, 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 cylinder 2 glow plug as necessary. The repairs will be made at no charge to the customer. |