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Service bulletins for the 2020 Chevrolet Tahoe

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.

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

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By component

By trouble code

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
20-NA-2072022-03-16. Service bulletin. PARKING BRAKE:ELECTRICAL:CONTROL MODULE; ELECTRICAL SYSTEM; POWER TRAIN. This service bulletin informs the technician to inspect for a possible electrical concern at the ECM X2 electrical connector to correct a customer concern of Malfunction Indicator Lamp (MIL) Illuminated - DTC P0333 Set.
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.
PIT5692A2022-03-14. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about how to diagnosis a battery draw that may be caused by a module back feeding voltage in the ignition relay circuits making the vehicle think it is still awake.
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.
N2223593202022-03-07. Service bulletin. ELECTRICAL SYSTEM. Service Update. On certain vehicles equipped with Police Package (RPO 9C1) and Content Theft Deterrent Disabled (RPO UTQ), the auxiliary battery may become discharged during extended operations, and using the installed special equipment. When the auxiliary battery state of charge diminishes below a defined voltage level, the installed special equipment will shut down. Dealers are to reprogram the body control module.
20NA1322021-12-20. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
PIT5466D2021-10-25. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician to help converting vehicles to fleet key option Regular Production Option Code 6E2 or 6E8. Technician will need to check the Regular Production Option Code for 6E2 or 6E8. Technician will need to order the correct key part number per the Regular Production Option Code. Then the technician will need re-code the lock cylinders to match the Regular Production Option Code. Also replace the Body Control Module and normal Service Programming System to the Body Control Module will turn the vehicle to a common key.
PIT5317D2021-09-13. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communication provides information to the technician about vehicles with the rear body fuse block with a loose fuse connection. Technician will need to check terminal tension on the rear fuse block. Technician will need to replace the rear body fuse block if poor terminal tension is the issue. Technician will need to replace the appropriate terminated lead if something other than the main power buss bar has poor terminal tension.
PIT5509H2021-09-13. Service bulletin. AIR BAGS; TRAILER HITCHES; ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System? message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
PIT5698B2021-09-13. Service bulletin. ELECTRICAL SYSTEM:ADAS:BLINDSPOT:SENSORS. This Preliminary information communicates additional information on how a LIN bus operates and diagnostic tips when working on a LIN bus.
PIT5509H2021-09-13. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System? message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
21NA0772021-07-19. Service bulletin. ELECTRICAL SYSTEM. This informational bulletin provides information for dealers/technicians on Aero Shutter Related Diagnostic Codes.
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.
18NA2792021-07-19. Service bulletin. LATCHES/LOCKS/LINKAGES; ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on the process to disable and enable passive unlocking.
21NA1242021-07-06. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set.
PIP5733R2021-05-17. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
21NA0612021-05-10. Service bulletin. ELECTRICAL SYSTEM:IGNITION:ANTI-THEFT:IMMOBILIZER/PROXIMITY:KEY/SENDER. This service bulletin provides information for dealers on Using EL-52545 When Diagnosing PEPs Transmitter Key Fobs (North America ONLY).
20NA1322021-05-03. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
20NA1232021-05-03. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides repair information to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated with DTCs U1961, U1983 setting.
PIT5745B2021-04-19. 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.
20NA2122021-02-22. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. This technical bulletin provides repair information to correct a customer concern of IPC Gauges Inoperative or Fluctuate, No Crank, Start then Stall.
PIT5799A2021-02-16. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates a cocnern where a flashing spot can intermittently show up on the radio display while in reverse. The PI advises that engineering is investigating the concern.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
20NA2122020-12-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; SUSPENSION; ELECTRICAL SYSTEM; ENGINE. This technical bulletin provides repair information to correct a customer concern of IPC Gauges Inoperative or Fluctuate, No Crank, Start then Stall.
20NA1232020-12-21. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides repair information to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated with DTCs U1961, U1983 setting.

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