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Service bulletins for the 2021 Chevrolet Blazer

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.

814 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
PIT5847A2021-09-13. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This Preliminary information communicates that a vehicle may come into the dealer with various concerns which may include a service engine light or various warning messages on the DIC. The technician is instructed to inspect a wiring harness for chaffing on a bracket which is located beneath the battery tray. If damage to the harness is found the technician is instructed to repair the damaged wiring and secure the harness away from the bracket so that future damage to the harness will be eliminated.
21NA1472021-08-09. Service bulletin. ELECTRICAL SYSTEM:IGNITION:COIL:SPARK PLUGS; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE AND ENGINE COOLING. This service bulletin provides a repair procedure to correct a customer concern of Coolant and/or Oil Leak, Malfunction Indicator Lamp (MIL) Illuminated?.
21NA1392021-08-09. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM). This service bulletin provides a repair procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3055 Set.
21NA1182021-07-19. Service bulletin. ENGINE. This technical bulletin provides a procedure to align the exhaust causing a vibration.
21NA1082021-07-19. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING. This service bulletin provides diagnostic information for the technician regarding a customer concern of engine overheating, cooling system contaminated with engine oil.
21NA0882021-07-19. Service bulletin. ENGINE. This service bulletin provides repair information to correct a customer concern of a Check Engine Light Displayed on Driver Information Center (DIC), Engine Cooling Fan Windmilling, DTC P0494 Set.
19NA2562021-07-19. Service bulletin. ENGINE. This service bulletin provides diagnostic aid procedure to perform inspections to determine if the engine needs to be replaced as opposed to just internal parts for knocking, rattle, squeak and/or squeal type noises from engine.
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.
21NA1182021-07-06. Service bulletin. ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to align the exhaust causing a vibration.
21NA1082021-07-06. Service bulletin. UNKNOWN OR OTHER; ENGINE AND ENGINE COOLING. This service bulletin provides diagnostic information for the technician regarding a customer concern of engine overheating, cooling system contaminated with engine oil.
21NA0882021-07-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides repair information to correct a customer concern of a Check Engine Light Displayed on Driver Information Center (DIC), Engine Cooling Fan Windmilling, DTC P0494 Set.
19NA2562021-07-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides diagnostic aid procedure to perform inspections to determine if the engine needs to be replaced as opposed to just internal parts for knocking, rattle, squeak and/or squeal type noises from engine.
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.
PIP58042021-06-14. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates the possibility of a inaccurate #1 Coolant Temperature Sensor causing the engine to run hot or overheat with possible over temperature message displayed on DIC
PIE06302021-06-07. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to air conditioning repairs, or other repairs the require the evacuation of the a/c refrigerant.
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.
PIT5834A2021-05-17. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING. This preliminary information addresses the possibility for the air conditioning to be slow to cool the cabin due to contamination in the refrigerant.
PIP5803A2021-05-17. Service bulletin. EQUIPMENT; ENGINE. This Preliminary information communicates to technician's if they remove the front timing cover when performing a repair, they should inspect the timing chain guide upper bolt for being loose. This document is an attempt to collect parts so engineering can investigate the concern.
PIT58342021-05-17. Service bulletin. ENGINE AND ENGINE COOLING. This preliminary information addresses the possibility for the air conditioning to be slow to cool the cabin due to contamination in the refrigerant.
PIT5825B2021-05-17. Service bulletin. SUSPENSION; BACK OVER PREVENTION; ENGINE AND ENGINE COOLING. This Preliminary information communicates information regarding a Vibration Type Noise from the metal gasket tabs between the front exhaust and muffler.
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.
PIT5825A2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING; BACK OVER PREVENTION; SUSPENSION. This Preliminary information communicates information regarding a Vibration Type Noise from the metal gasket tabs between the front exhaust and muffler.
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.
PIT58252021-04-19. Service bulletin. SUSPENSION; BACK OVER PREVENTION; ENGINE AND ENGINE COOLING. This Preliminary information communicates information regarding a Vibration Type Noise from the metal gasket tabs between the front exhaust and muffler.
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.

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