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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 are shown. Show all

Bulletins, newest first
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.
19NA1042021-12-27. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT. This service bulletin provides information for dealers/technicians and customers on steam/vapor coming from the front grille or radiator area.
20NA0282021-12-20. Service bulletin. ENGINE AND ENGINE COOLING:COOLING SYSTEM. This service bulletin is to inform dealers that in extreme cold weather, a grille winter cover needs be added during PDI to avoid the customer returning with concerns related to charge air cooler icing.
18NA0732021-12-20. Service bulletin. ENGINE. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
PIP58292021-12-13. Service bulletin. ENGINE; EQUIPMENT. This Preliminary information communicates to the dealers information related to diagnosis of a MIL illuminated with DTC P0299.
PIP5826A2021-12-13. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
PIP58262021-12-13. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
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.
A2123346702021-08-09. Service bulletin. EQUIPMENT; ENGINE; EQUIPMENT ADAPTIVE/MOBILITY. Service Update. Certain vehicles equipped with a 1.3L gasoline engine (RPO L3T), have cylinder head outer bolts which were not tightened. Dealers are to retighten the cylinder head outer bolts.
19NA0442021-07-19. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides information on the cold start control system in DI engines to reduce cold start emissions and improve fuel economy.
20NA2182021-07-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
19NA0442021-07-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides information on the cold start control system in DI engines to reduce cold start emissions and improve fuel economy.
A202317281 022021-06-14. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR. Emission Recall. Certain vehicles with a 1.2L engine (RPO LIH) may have received incorrect catalytic converter parts that do not meet all emission system requirements. Dealers are to inspect the catalytic converter and replace if the correct part was not installed.
000601026N2021-06-07. Service bulletin. ENGINE. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
20NA1382021-05-03. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
20NA0242021-05-03. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides a information and diagnostic steps/tips for vehicles that are slow to heat up in cold temperatures.
PIP5712B2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR; POWER TRAIN. This Preliminary information communicates to the technician a service Diagnostic / Repair tip to avoid causing the crankshaft sprocket to disengage from the crankshaft during crankshaft balancer or cam drive system component related service procedures.
PIP5712A2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR. This Preliminary information communicates to the technician a service Diagnostic / Repair tip to avoid causing the crankshaft sprocket to disengage from the crankshaft during crankshaft balancer removal.
21NA0142021-03-01. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM; EQUIPMENT. This technical bulletin provides a procedure to relocate the ground wire from the G58 Emission Purge Pump to the engine block directly to correct the customers concern.
18NA0732021-03-01. Service bulletin. ENGINE. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
090604026S2021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE; EQUIPMENT. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
010601011L2021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION; EQUIPMENT. This informational bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
20NA0842021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides information on normal engine characteristics/noise produced by the LIH engine.
20NA0282021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin is to inform dealers that in extreme cold weather, a grille winter cover needs be added during PDI to avoid the customer returning with concerns related to charge air cooler icing.
090604026S2021-02-01. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; ENGINE AND ENGINE COOLING. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.

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