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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: Electrical system are shown. Show all

Bulletins, newest first
PI0592G2022-10-13. Service bulletin. ELECTRICAL SYSTEM. This preliminary information (PI) provides information om Service Programming System (SPS) Error Codes (E4398, E4399, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491 or E6961).
13-08-116-001H2022-10-11. Service bulletin. ELECTRICAL SYSTEM. The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
21-NA-0682022-10-07. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This warranty administration bulletin provides policy information requirements applicable to key fob replacement under the New Vehicle Limited Warranty or under a Replacement Parts Warranty on 2017-2022 and newer model year vehicles with RPO ATH and AVJ.
PIT5569B2022-08-15. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT; SERVICE BRAKES, AIR:ANTILOCK:WHEEL SPEED SENSOR. This Preliminary information communicates direction and examples when diagnosing multiple DTCs, one of which includes U**** Byte 71 DTC.
22-NA-1072022-08-03. Service bulletin. ELECTRICAL SYSTEM:IGNITION; POWER TRAIN. This service bulletin provides repair information to correct a customer concern of a Service AWD Message in DIC at Ignition On with DTC C056D Set.
22-NA-0942022-07-12. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This service bulletin provides repair information to correct a customer concern of a loss of cabin heat.
22-NA-1152022-07-12. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This service bulletin provides information for U.S. dealers ONLY to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require attention.
22NA0232022-06-21. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. This service bulletin provides repair information to correct a customer concern of Instrument Cluster DIC Displays Programming in Progress Message and Progress Bar.
21NA0242022-06-21. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:APPLIANCE:AIR CONDITIONER; ENGINE. This technical bulletin provides repair information to correct a customer concern of Service Engine Soon MIL Illuminated with DTC P2B87 Set.
PIT5847D2022-06-13. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN. 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, at a transmission stud and at the transmission oil cooler line bracket. 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.
PIT5745D2022-06-13. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates and issue with the memory seat module waking up the low speed GM lan bus and causing a battery draw.
21-NA-1832022-06-09. Service bulletin. ELECTRICAL SYSTEM; EXTERIOR LIGHTING; EQUIPMENT. This service bulletin provides repair information to correct a customer concern of Intermittent Door Locks Inoperative, DTCs B3125, B3130, B3135, B3979, B3980, Various U codes, IP Lamps Illuminate, Immobilizer, Unwanted Horn or Hazard Flasher Operation.
22-NA-1152022-06-06. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This service bulletin provides information for U.S. dealers ONLY to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require attention.
22-NA-1072022-06-04. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION. This service bulletin provides repair information to correct a customer concern of a Service AWD Message in DIC at Ignition On with DTC C056D Set.
22NA0122022-05-31. Service bulletin. ELECTRICAL SYSTEM:ADAS:PARKING ASSIST:SENSORS. This service bulletin provides information for dealers/technicians on Stone Chip/Membrane Damage, Broken Connector and/or Sensor Retaining Tabs, and/or Paint Damage of Park Assist Sensors.
PIT5847C2022-04-18. Service bulletin. ENGINE; ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. 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.
PIP4670J2022-04-18. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about a no start or another concern after swapping an Engine Control Module or other modules from one vehicle to another. The Global Architecture electrical system associated with these vehicles does not allow controller swaps between vehicles.
19-NA-0762022-04-05. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides repair information to correct a customer concern of Blue or Black Screen and Service Rear Vision System Message on Radio Display Shifting into Reverse.
21-NA-0362022-03-30. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; EQUIPMENT. This service bulletin advises the technician of a diagnostic test for a possible issue with a damaged OCV solenoid that may cause an oil leak and misfire, illuminating the MIL and setting DTCs P0300, P0302 and/or P0305.
PIC64502022-03-14. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates a process to correct the concern of Unable to contact OnStar after the 3G EOL on 2015-2022 model year vehicles in the United States.
PIT5745C2022-03-14. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates and issue with the memory seat module waking up the low speed GM lan bus and causing a battery draw.
21NA2562022-02-14. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); EXTERIOR LIGHTING. This service bulletin provides repair information for dealers/technicians to correct a customer concern of a Malfunction Indicator Lamp Illuminated with DTC P26BB Set.
21NA2792021-12-27. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides a procedure to replace the starter if found the cause of the rattle noise.
21NA2782021-12-27. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This service bulletin provides diagnostic strategy information to aid in diagnosing a Ticking, Tap or Rattle Noise from Engine with Possible Misfire, Malfunction Indicator Lamp (MIL) Illuminated.
21NA2762021-12-27. Service bulletin. ELECTRICAL SYSTEM; ENGINE; EQUIPMENT. This service bulletin provides a procedure to correct a customer concern of Starter Not Cranking Engine, Grinding Noise When Starting?.

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