Service bulletin 21NA257

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)
Type	Service bulletin
NHTSA id	10207917
Published by NHTSA	2022-02-14
Manufacturer's number	21NA257
Manufacturer's date	2021-12-14
NHTSA component	EXTERIOR LIGHTING; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM)

NHTSA's summary

This service bulletin provides a service procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3075 Set.

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, Lighting, Engine control module

Trouble codes named

P3075

Vehicles listed
BUICK ENCORE GX	2020, 2021, 2022
CADILLAC CT4	2020, 2021, 2022
CADILLAC CT5	2020, 2021, 2022
CADILLAC XT4	2019, 2020, 2021, 2022
CADILLAC XT5	2020, 2021, 2022
CADILLAC XT6	2020, 2021, 2022
CHEVROLET BLAZER	2019, 2020, 2021, 2022
CHEVROLET MALIBU	2019, 2020, 2021
CHEVROLET SILVERADO 1500	2019, 2020, 2021, 2022 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET TRAILBLAZER	2021, 2022
GMC ACADIA	2020, 2021, 2022
GMC SIERRA 1500	2019, 2020, 2021, 2022 (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.

Recalls for the same vehicles and component
21V346000	2021-05-13. 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
PIT5687A	2024-02-12. 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.
N232412712	2023-12-06. Service bulletin. Service Update - Certain vehicles with a 2.0L engine have an Engine Control Module (ECM) that may not properly diagnose, may not set Diagnostic Trouble Codes (DTCs), or may not illuminate the Malfunction Indicator Light (Check Engine Light) if certain fault conditions of the catalytic converter were to occur. Owners who have accepted applicable terms and conditions will have the opportunity to accept these software changes using wireless over-the-air (OTA) technology without having to bring their vehicle to a dealership. Alternatively, owners may have their vehicle serviced at a GM dealer to receive these software updates. Dealers are to reprogram the ECM.
N222383020	2023-07-25. Service bulletin. Service Update: Certain vehicles may have an Engine Control Module that does not properly respond to certain service tool requests for the datafile CALID (part number) and CVN (checksum). This condition may cause a vehicle to fail an emissions Inspection/Maintenance (I/M) test. Dealers are to reprogram the Engine Control Module.
PIP5628F	2023-05-15. 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
N212351211	2023-03-08. Service bulletin. General Motors has decided to conduct a voluntary emissions recall involving certain vehicles, equipped with a diesel engine. The Engine Control Module (ECM) may not properly detect faults, set DTCs or illuminate the Malfunction Indicator Light (Check Engine Light) if these fault conditions occur: •Charge Air Cooler (CAC) low efficiency (DTC P026A) •Exhaust Gas Recirculation (EGR) cooler low efficiency (DTC P2457) •NOx sensor position 1 slow response (DTC P22F9) Dealers are to reprogram the Engine Control Module (ECM) with corrected software.
N222372592	2023-01-07. 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.
21NA113	2022-06-21. Service bulletin. This technical bulletin provides a procedure to perform a learn procedure for the turbo actuator.
20NA165	2022-06-21. Service bulletin. This technical bulletin provides repair information to correct a customer concern of Flutter or Boom Noise at 1200 RPM- Service Calibration.
20NA090	2022-06-21. Service bulletin. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
18348	2022-05-31. Service bulletin. Service Update. Some vehicles may set DTC P189D and display SERVICE SHIFTER SEE OWNER?S MANUAL on the Driver Information Center (DIC). When this message is displayed, the vehicle will go into N (Neutral) once the vehicle?s speed is below 6 mph (10 km/h), and then into P (Park) once the vehicles speed goes below 3 mph (5 km/h). The customer will be able shift and drive the vehicle per instructions in the vehicle Owner?s Manual. Dealers are to reprogram the engine control module (ECM) with an updated software and calibration.