I live in [XXX], where summer temperatures are extremely high. This week, afternoon temperatures have been reaching nearly 100°F (38°C). My vehicle is a mild-hybrid Volvo XC40, and there is no option to permanently disable the automatic start-stop function (or at least every time I start the car). This week, while driving home from work at around 4:00 PM, I stopped at a traffic light and the engine shut off automatically. As a result, the air conditioning immediately reduced its cooling performance, making the cabin noticeably less comfortable in the extreme heat. I instinctively pressed the accelerator to turn the engine back on and I nearly collided with the vehicle in front of me. In my opinion, this creates a genuine safety concern. Volvo should provide drivers with the ability to disable the automatic start-stop feature through a software setting. While the system is intended to reduce emissions and improve fuel economy, drivers should be able to decide when those benefits are appropriate and when safety, comfort, or local driving conditions make continuous engine operation the better choice. A permanent on/off setting would allow owners to use the feature when desired while avoiding situations where the automatic engine shutdown negatively impacts driving safety or cabin comfort. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Source: NHTSA complaint ODI #11753925 · view all complaints for this vehicle at nhtsa.gov

Mild hybrid vehicle that was purchased 4/20/2026. Volvo service states incident on 06/10/2026 was caused by vehicle running overnight in enclosed garage. Volvo also states that cause was due to item inserted into drivers seatbelt buckle. No warnings posted regarding this would cause the vehicle to turn on once car was parked and driver door shut and run continuously throughout the night in an enclosed garage. Volvo claims every time the driver door is opened, it shuts the engine off. This is not true! And this situation proves that. Vehicle still currently at dealers to be repaired so unsure if components are available for inspection. Components damaged are: Midvoltage battery, midvoltage Converter module, starter generator module, 12v battery. The vehicle became extremely hot and would have caught on fire had our smoke/co detector not gone off. CO was detected in house and garage. Volvo refusing to take any accountability for this situation and refusing to provide me the documentation for the findings of my vehicle.

Source: NHTSA complaint ODI #11751346 · view all complaints for this vehicle at nhtsa.gov

The car starts vibrations on at 70 mph through 80 mph. I have brought it to the dealer who stated they felt it and declared that it is normal for severe vibrations to occur at only these speeds. Volvo refused to acknowledge or treat the issue. This issue has been reported and Volvo issued a Technical Journal 36752.2.0 which directs the technicians to acknowledge the vibrations but will provide no solution. This is a safety issue if your car vibrates at highway speed. How has Volvo been allowed to sell these cars without warnings?

Source: NHTSA complaint ODI #11736610 · view all complaints for this vehicle at nhtsa.gov