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Service bulletin 20NA218

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10187763
Published by NHTSA2021-03-01
Manufacturer's number20NA218
Manufacturer's date2021-01-15
NHTSA componentEQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE

NHTSA's summary

This technical bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.

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

Engine, Equipment and accessories, Engine control module

Trouble codes named

P12A6

Vehicles listed
CADILLAC ESCALADE ESV2021
CADILLAC ESCALADE NA2021 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET CORVETTE2020
CHEVROLET SILVERADO 15002019, 2020 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 25002020 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 35002020 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SUBURBAN2021
CHEVROLET TAHOE2021
GMC SIERRA 15002019, 2020 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 25002020 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 35002020 (the catalog's model; the bulletin names a series or trim of it)
GMC YUKON2021
GMC YUKON XL2021

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
21V3460002021-05-13. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
PIT5687A2024-02-12. Service bulletin. This Preliminary information communicates some diagnostic tips to inspect for no/low voltage at the ECM for a customers complaints of a SES MIL, Crank No Start, stalling DTC's: P16A7 and/or P16AF.
PIP5628F2023-05-15. Service bulletin. This Preliminary information communicates information that will need to be provided to TAC to aid in diagnosing if a vehicle comes in with misfire and DTC Codes P0300 - P0308 and/or P050D
N2123551402023-01-24. Service bulletin. Service Update Bulletin - Certain vehicles may have a condition where the engine control module has an incorrect calibration. Dealers are to reprogram the engine control module.
N2223725922023-01-07. Service bulletin. Service Update. Certain vehicles may have a condition in which ice or sludge can accumulate in the Charge Air Cooler (CAC) or Closed Crankcase Ventilation (CCV) system when driving in extremely cold weather conditions (-18°C (0°F) or less). Dealers will install a radiator air front lower baffle and, if necessary, reprogram the Engine Control Module.
21NA1132022-06-21. Service bulletin. This technical bulletin provides a procedure to perform a learn procedure for the turbo actuator.
20NA0902022-06-21. Service bulletin. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
20NA2282022-05-31. Service bulletin. This technical bulletin provides a procedure to replace the fuel filter and perform a filter life procedure if found the reason for a failed fuel filter life reset during ECM transfer of data.
20NA1972022-05-31. Service bulletin. This technical bulletin provides a procedure to inspect and repair the fuel pressure sensor if found the cause of the customers concern.
20NA1892022-05-31. Service bulletin. This technical bulletin provides repair information to correct a customer concern of Transmission Control Module Offline Event.
21NA2572022-02-14. Service bulletin. This service bulletin provides a service procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3075 Set.