WenmarOpen by Wenmar Pro

Service bulletins for the 2021 Chevrolet Trailblazer

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.

753 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Only bulletins with component: Engine control module are shown. Show all

Bulletins, newest first
PIP5628F2023-05-15. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM). 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
20NA1652022-06-21. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin provides repair information to correct a customer concern of Flutter or Boom Noise at 1200 RPM- Service Calibration.
21NA2572022-02-14. Service bulletin. EXTERIOR LIGHTING; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM). This service bulletin provides a service procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3075 Set.
21NA2152021-12-27. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM). This technical bulletin provides a procedure to correct a customer concern of a Pop Noise Heard on Heavy Acceleration Only.
A2023219902021-08-09. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); EQUIPMENT; ELECTRICAL SYSTEM. Service Update. Certain vehicles may have engine control module software that leads to erroneous additional fuel enrichment under rare driving conditions. Dealers are to reprogram the engine control module.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.