On certain trucks, the driver may be able to turn off the daytime running lamps (DRLs) while driving. Canadian regulations require that DRLs must stay on while driving, unless the headlamps or fog lamps are switched on.
Safety Risk
Driving without daytime running lights could make the vehicle less visible to others and increase the risk of a crash.
Corrective Actions
PACCAR will notify owners by mail and instruct you to take your truck to a dealer to update the vehicle software.