DETROIT (AP) — General Motors is recalling over 368,000 pickups and other trucks worldwide after 19 reports of fires caused by engine block heater cords.

The recall covers certain 2019 Chevrolet Silverado 4500, 5500 and 6500 trucks, as well as the 2017 through 2019 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500. All have GM’s 6.6-Liter diesel engines and an optional engine block heater used to keep the block warm in extremely cold temperatures.

GM is asking customers not to use engine block heaters until further notice. The company said Friday that the electric heater cord or the terminals connecting the cord to the heater could short-circuit and fail. That can cause fires. No injuries have been reported.

GM is still trying to find the cause of the problem and develop a fix. The company began investigating the problem in December and found that a fire can occur if a block-heater coolant leak develops and the coolant comes in contact with the cable terminals, or if the cable itself is damaged.

About 324,000 U.S. trucks are covered by the recall.

GM began notifying dealers on April 26 and told them to stop selling the trucks until repairs are made. No date has been set yet to notify owners.