Complaint 2204126

Complaint Summary

FUEL/PROPULSION SYSTEM

Owner Narrative

My 2023 GMC Hummer EV 3X has experienced repeated thermal-protection failures in the high-voltage battery and drive-motor cooling system, causing the vehicle to enter limp mode and drop to as low as 12 mph without warning. Stored fault codes: P0C12, P0C13, P2EE0, P2EE1 (battery and drive-unit overheating). A sudden, unannounced drop to 12 mph in a 9,000-lb EV is a serious safety hazard — on highways it creates rear-end collision risk, in intersections it leaves the vehicle stranded in traffic, and on remote roads it can strand the driver with no safe shoulder. Visit 1 (Covert Buick GMC of Bee Cave, TX): 02/09/2026–03/24/2026, 43 days out of service. Repairs: replaced both EV coolant pumps (PN 85605761), replaced Drive Motor Inverter Module 2 (PN 24059125), coolant flush, software update. RO #BUCS138101. GM TAC Case #88689105. Six days after return, on 03/30/2026, the same defect recurred with the same fault codes. Vehicle has now been back at the dealer 38+ additional days with no resolution. GM had pre-sale knowledge of this exact defect on this exact VIN. The vehicle was a GM corporate evaluation unit (factory option code OAR — EVALUATION VEHICLE) operated out of GM Tech Center in Warren, MI. GM took it out of service on 08/07/2025 at 30,169 miles. I took delivery 16 miles later at 30,185 miles. A GM Driver Inspection Form left inside the vehicle at delivery is handwritten with "Limited Speed 12 mph" — the exact limp-mode behavior. GM auctioned the vehicle through CVO Warren Distribution Center without disclosing this condition. I request ODI open a preliminary evaluation of cooling-system thermal-protection failures on 2022–2024 Hummer EV Pickups and SUVs, particularly units with prior corporate/fleet use.

Owner-submitted narrative on file with NHTSA. Complaint narratives are self-reported and have not been verified.