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Service bulletins for the 2026 GMC Hummer EV SUV

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.

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

By type

By component

By trouble code

Bulletins, newest first
661.202026-04-01. Over-the-air update. UNKNOWN OR OTHER. • Improvements to the performance of vehicle software updates. • Fixes to help prevent loss of functionality for connectivity features, including maps and Wi-Fi. • Fixes to help prevent erroneous emergency calls from vehicle. • Fixes to help ensure proper functionality for mobile app features. • Improvements to the performance of Super Cruise.
661.102026-04-01. Over-the-air update. UNKNOWN OR OTHER. • Improvements to help protect battery health in low temperatures. • Improvements to diagnostics to reduce service messages. • Fixes to help protect battery health in high temperatures. • Fixes to improve responsiveness for vehicle diagnostics.
N2525290802026-04-01. Service campaign. ELECTRICAL SYSTEM. Service Update. Certain vehicles listed above may be missing a high voltage header plug on the RESS battery pack drive motor connector. Dealers are to inspect the RESS pack connectors and install the proper HV Header Plug if missing.
PIP61042026-03-17. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
PIP4902V2026-03-17. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT6393J2026-03-11. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information is to inform customers to follow diagnostics if resetting, disconnecting the module did not correct it.
PIT6425D2026-03-11. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC'ss
PIC6629C2026-03-11. Service bulletin. UNKNOWN OR OTHER. This PI is to instruct dealer on diagnostic procedures that need to be completed prior to replacing a radio or IPC display
N2525415102026-03-03. Service campaign. UNKNOWN OR OTHER. Certain vehicles may have been sold with a GM NACS Level 2 EV charging adapter (NACS to J1772) in which a quality issue was identified. Dealers are to provide the customer with the latest design charging adapter.
PIP6081B2026-03-03. Service bulletin. UNKNOWN OR OTHER. This Pi is to let dealer know that a program issue has been released and to not replace any hard for codes P2C8A, P2C8B, U3577, U3578, U3579, U357A, U357B, U357C, U357D, U357E, U357F, U3580, U3581, U3582, U3583, U3584, U2BAA, U2BAB, U2BAC, U2BAD, U2BAE,
PIT6456D2026-02-23. Service bulletin. UNKNOWN OR OTHER. This preliminary information communicates an issue with the key fob buttons inoperative and how to resync the fobs back to the vehicle.
PIT6213D2026-02-23. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates that the Tailgate Assist Handle is not included with certain truck models and how to get one if needed.
PIC66382026-02-01. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to the technician the repair direction needed to address an inaccurate speed limit sign displayed on instrument cluster.
PIC6638A2026-02-01. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to the technician the repair direction needed to address an inaccurate speed limit sign displayed on instrument cluster.
PIT5985K2026-02-01. Service bulletin. UNKNOWN OR OTHER. This PI provides diagnostics tips to dealership techs when trying to diagnose a CAN Bus communication issue after an event like a lightning strike, battery jump started backwards, failure over the air update, etc.
PIP60982026-01-19. Service bulletin. UNKNOWN OR OTHER. This PI advised dealer technicians of possible causes of diesel fuel contamination in gasoline powered vehicles and advises of warranty direction.
PIT6425C2026-01-19. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's
PIT6457B2026-01-19. Service bulletin. UNKNOWN OR OTHER. This preliminary information is for technicians that may see DTCs that are history and should not perform any part replacements. They should follow the notes mentioned prior to anything being replaced.
PIP4902U2026-01-13. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIC6540F2026-01-04. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealers a procedure to reset the radio.
PIT6393H2025-12-29. Service bulletin. UNKNOWN OR OTHER. "This Preliminary Information is to inform customers to follow diagnostics if resetting, disconnecting the module did not correct it. It also informs them to follow the bulletins as necessary to USB update the modules."
PIT6445B2025-12-22. Service bulletin. UNKNOWN OR OTHER. This PI communicates information that the Collision / Detection Systems will revert to default setting of Alert and Brake after an Ignition Cycle due to an Engineering change.
PIT6457A2025-12-15. Service bulletin. UNKNOWN OR OTHER. This preliminary information is for technicians that may see DTCs that are history and should not perform any part replacements. They should follow the notes mentioned prior to anything being replaced.
PIC6629B2025-12-15. Service bulletin. UNKNOWN OR OTHER. This PI is to instruct dealer on diagnostic procedures that need to be completed prior to replacing a radio or IPC display
PIT6393G2025-12-08. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information is to inform customers to follow diagnostics if resetting, disconnecting the module did not correct it. It also informs them to follow the bulletins as necessary to USB update the modules.

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