Buick Enclave 2017–2021 — technical service bulletin

Bulletin 21-NA-139 · NHTSA communication 11017443 · issued Apr 2, 2025

Technical service bulletin

communication type

Engine

component

2017–2021

model years

vehicle entries

Official summary

This service bulletin provides a repair procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3055 Set.

Vehicles covered

2017 Buick Enclave
2018 Buick Enclave
2019 Buick Enclave
2020 Buick Enclave
2021 Buick Enclave
2017 Buick Lacrosse
2018 Buick Lacrosse
2019 Buick Lacrosse
2020 Buick Lacrosse
2018 Buick Regal
2019 Buick Regal
2020 Buick Regal
2018 Buick Regal Tourx
2020 Buick Regal Tourx
2017 Cadillac CT6
2018 Cadillac CT6
2019 Cadillac CT6
2019 Cadillac XT4
2020 Cadillac XT4
2021 Cadillac XT4
2018 Cadillac XT5
2019 Cadillac XT5
2020 Cadillac XT5
2021 Cadillac XT5
2020 Cadillac XT6
2021 Cadillac XT6
2019 Chevrolet Blazer
2020 Chevrolet Blazer
2021 Chevrolet Blazer
2017 Chevrolet Cruze
2018 Chevrolet Cruze
2019 Chevrolet Cruze
2017 Chevrolet Malibu
2018 Chevrolet Malibu
2019 Chevrolet Malibu
2020 Chevrolet Malibu
2021 Chevrolet Malibu
2019 Chevrolet Silverado 1500
2020 Chevrolet Silverado 1500
2021 Chevrolet Silverado 1500
2018 Chevrolet Traverse
2019 Chevrolet Traverse
2020 Chevrolet Traverse
2021 Chevrolet Traverse
2018 GMC Acadia
2019 GMC Acadia
2020 GMC Acadia
2021 GMC Acadia
2019 GMC Sierra 1500
2020 GMC Sierra 1500
2021 GMC Sierra 1500

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.