PACCAR issued a recall on the T300T600, and T800 models

On certain trucks, the trailer light wiring harness may have been routed incorrectly during vehicle assembly. This could cause the wires within the harness plug to be pulled away from the chassis plug, resulting in an intermittent or complete electrical power loss to the trailer. This would cause a loss of all trailer lighting and ABS function. Inoperative side markers and tail lamps would make the trailer less visible to other drivers during times of reduced visibility. A loss of brake lamp function would not allow a following driver to know when the brakes have been applied, and a rear-end crash could occur as a result. Correction: Dealers will re-route the wiring harness.