https://cleantechnica.com/2019/05/11/gm-recalls-368000-pickup-trucks-because-of-...

General Motors announced last week it is recalling 368,000 of those trucks. Why? Because diesel engines are beastly hard to start in cold weather. Diesel fuel is not very volatile. In fact, you can drop a burning match into a tub of diesel and nothing happens. It also has a lot of wax in it, which tends to congeal when temperatures turn frigid.
The best way to deal with the cold weather starting problem is to install an electric engine heater to ward off the worst effects of the cold. Plug it in and all the internals of the engine will be toasty warm at oh-dark-hundred when it’s time to fire up your truck and head off to work.
The problem for GM is that a wiring defect in the engine heaters installed in some of those medium and heavy duty trucks can lead to fires under the hood. According to NBC News, the recall covers trucks equipped with the optional engine block heater

Vehicles still have a long way to go before fires become a thing of the past.....