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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

Bulletins, newest first
PIP5691B2020-10-19. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication advises the technician that the engine exchange program on vehicles equipped with engine Regular Production Option Code L3T has ended. This engine can now be ordered through the regular General Motors Customer Care and Aftersales parts process or Product Quality Center process for required dealers.
20NA1592020-09-28. Service bulletin. TIRES. This Warranty Administration bulletin is for information on General Motors New Vehicle Tire Warranty Program (U.S. Dealers Only).
20NA1572020-09-28. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides information on the Transport Mode On Message Being Displayed in the Driver Information Center (DIC) and/or Battery Light is Flashing and the procedures to turn the Transport Mode message ON and OFF.
16NA3612020-09-28. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This informational bulletin explains possible normal condition of a flare from 1st to 2nd, even if the trans had been repaired for the flare and its still noticed.
PIP57462020-09-14. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. This Preliminary information communicates the possibility of the vehicle having dtc P2B95 in history and possibly P2B96 P2B0A, P2B08, or P2B09 due to a software anomally.
20NA1512020-08-31. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct conditions of Engine Idle Unstable, Malfunction Indicator Lamp (MIL) Illuminated - DTC P0011, P0014, P0016, P0017, P05CC and/or P05CE Set.
20NA1352020-08-31. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Power Liftgate and/or Instrument Panel Cluster (IPC) Inoperative, No Audio, Malfunction Indicator Lamp (MIL) Illuminated - DTC P159F-00, U0184-00, U0198-00 and/or U1501-00 Set.
20NA0282020-08-31. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ENGINE AND ENGINE COOLING:COOLING SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin is to notify dealership personnel as well as providing the customer with the usage instructions from the owner manual, that in extreme cold weather (-18°C or less / 0°F or less), a grille winter cover needs be added during PDI to avoid the customer returning with concerns related to charge air cooler icing.
PIP5675E2020-08-10. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer that a customer may comment that the MIL light is illuminated. The technician may find P1098 and/or P26BB set current or history. That this may be caused by a software anomaly, and that GM is currently looking into the issue. It provides testing and related direction based on the results.
PIP5704D2020-08-10. Service bulletin. STRUCTURE. This Preliminary information communicates a work around when only 11 digit PUN (Part Unique Number) is seen on Service Solenoid Body Assembly.
PIP57392020-08-10. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates specific directions for the application of room temperature vulcanizing (RTV) sealant to the engine Lower Crankcase Extension during engine oil pan installation.
PIP57342020-08-10. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION:PUMP; FUEL SYSTEM, GASOLINE. This Preliminary information communicates to the dealer a testing procedure to isolate a potential Engine Oil Pump Switching issue.
20NA1352020-08-10. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of check engine lamp illuminated, DTC P159F 00 set, No Audio.
20NA1222020-08-10. Service bulletin. STRUCTURE:BODY:HATCHBACK/LIFTGATE:SUPPORT DEVICE/STRUT. This informational bulletin provides Information on Proper Liftgate Adjustment.
20NA1212020-08-10. Service bulletin. STRUCTURE. This technical bulletin provides a procedure to locate and fix a possible leak in the roof area due to missing sealant.
20NA1202020-08-10. Service bulletin. POWER TRAIN. This informational bulletin explains how to check if the pulley and/or drive chain has any damage caused by low fluid or a code set that causes the transmission to default maxing out pressure.
A202299960 012020-07-20. Service bulletin. POWER TRAIN. Service Update - The gear shift lever may have a detent feel between Park and Reverse caused by the fastening bolt that is not fully seated and contacting the shifter housing. Dealers are to inspect the detent feel of the transmission range selector lever and replace the select cable if necessary.
A2023048402020-07-20. Service bulletin. ENGINE; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. SUB - Certain 2020-2021 Buick Encore GX and 2021 Chevrolet Trailblazer vehicles may have a condition where the camshaft actuator oil control valve (OCV) center bolt could stick or bind. If this were to happen, it could cause a MIL light to illuminate on the dash (Service Engine Soon), setting diagnostic trouble codes (DTC?s) P0011 or P0014, the engine could run rough and have reduced power. Dealers will inspect for these DTC?s that could have been set by this condition, and pass or fail based on results.
A202302140 012020-07-20. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE. Service Update - On certain vehicles, the engine oil pump may be stuck due to foreign material, and diagnostic trouble codes (DTC) P0521, P06DE, P06DD could be set. Dealers are to perform the engine oil pump screening test and if necessary, replace the oil pump.
A2023012302020-06-29. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE; ENGINE. SUB - Certain 2021 model year Chevrolet Trailblazer, and 2020-2021 model year Buick Encore GX vehicles, equipped with a continuously variable ratio (CVT) transmission, may experience reduced launch performance during a quick exit from a stop/start event. DTC?s P0746 and P0776 may also set illuminating a Check Engine Light. The main pump in the CVT has a priming delay under certain conditions. Dealers will reprogram the transmission control module (TCM) with updated software.
19NA2002020-06-22. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin provides a procedure to replace the transmission auxiliary pump to correct a condition of start/stop inoperative, MIL illuminated w/DTC P2797.
16NA3832020-06-22. Service bulletin. ENGINE; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
PIC6416A2020-06-15. Service bulletin. STRUCTURE. This Preliminary information communicates to the dealer that if the service AWD (All-Wheel Drive) or AWD (All-Wheel Drive) Off messages are on and there is a history DTC of C15C9 SYM02 set then no repairs are to be made at this time, a software issue was found and Engineering is working on a permanent solution. If the DTC is setting current then published diagnosis needs to be followed.
PIP5675D2020-06-15. Service bulletin. AIR BAGS. This Preliminary information communicates to the dealer that a customer may comment that the MIL light is illuminated. The technician may find P1098 and/or P26BB set current or history. That this may be caused by a software anomaly, and that GM is currently looking into the issue. It provides testing and related direction based on the results.
090089002R2020-06-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before sold (prepping) to the customer.

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