Kenworth Truck Co. is recalling T680 and T880 models from 2018 to 2020 with tandem axles and a single parking brake that can malfunction in cold temperatures.
The signal from the parking brake pressure switch to the transmission controller may be delayed when cab temperature registers 25 degrees Fahrenheit. The four-tenths of a second delay could result in a crash or injury.
The pressure switch signals the cab controller whether the parking brake is set or released.
REPORTED BY DEALERSHIP
Kenworth learned about the issue from a dealership because one of the trucks lurched forward and struck a service bay door. The Paccar Inc. division is trying to find a root cause for the issue. Kenworth tested eight park brake switches and confirmed a signal delay at 25 degrees Fahrenheit. Further testing revealed the switch delay got longer as the temperature dropped.
A driver could notice the transmission selector indicating a forward or reverse gear. The parking brake icon would not illuminate. If the transmission selector is not moved to neutral before the service brake is released, the truck could inadvertently move.
The recall involves 1,837 trucks equipped with certain models of automated manual transmissions. Kenworth said all the recalled trucks could have the condition.
The National Highway Traffic Safety Administration recall number is 19V-275.