General Motors has issued a Technical Service Bulletin for a wide selection of 2019/2020/2021 model year vehicles that are experiencing a no-start or long crank condition. This includes the Chevy Silverado, GMC Sierra, Tahoe, Suburban, Yukon, and more.
Technical Service Bulletin: #20-NA-218
Updated: 2/5/2021
TSB #20-NA-218 Applies To:
- 2020 Cadillac CT5
- 2021 Cadillac Escalade & Escalade ESV
- 2020 Chevrolet Corvette
- 2019-2020 Chevrolet Silverado 1500
- 2020 Chevrolet Silverado HD
- 2021 Chevrolet Tahoe & Suburban
- 2019-2020 GMC Sierra 1500
- 2020 GMC Sierra HD
- 2021 GMC Yukon & Yukon XL
TSB #20-NA-218 Reported Conditions
Owners of the above-affected vehicle models may experience a no-start or unusually long crank condition during start. Technicians may also find that DTC (trouble code) P12A6 may also be set after this occurs.
TSB #20-NA-218 – Cause & Fix
General Motors Engineers have determined that a software bug/anomaly in the engine control module (ECM) is responsible for these potential issues.
Owners who experience a no-start or long crank condition can contact their dealership for a software update that includes reprograming the ECM.
Zane Merva is the Executive Editor of GM-Trucks.com and the President of the New England Motor Press Association (NEMPA). A veteran automotive journalist with over 26 years of experience, Zane is a designated ‘Car Talk’ Expert and has been a contributor to The Boston Globe. He possesses a unique evaluative perspective, having road-tested more than 2,000 vehicles across every major manufacturer. While he is a recognized authority on General Motors truck platforms—including the Silverado, Sierra, and Colorado—his expertise is grounded in decades of deep competitive analysis that few in the industry can match. His commentary has been featured by major OEMs and media outlets, including Hyundai and PR Newswire