The contact owns a 2015 Jeep Cherokee. The contact stated that the 4-Wheel Drive mode had become inoperable. The vehicle was taken to the dealer, where it was diagnosed that the PTU had failed. The dealer advised the contact to continue driving the vehicle until the PTU failed completely because the vehicle could only be repaired under warranty after a complete failure of the PTU. The contact stated that the vehicle had failed to shift into gears as needed and had rolled away while parked. The contact stated that the vehicle required the parking brake to be engaged while parked. The contact stated while driving from a complete stop, the vehicle suddenly stalled and revved temporarily in the middle of an intersection. The contact was able to resume driving. The vehicle was taken to the dealer, where the failure could not be duplicated. The contact stated that while driving to the dealer the following day, the failure recurred, and the vehicle made abnormal sounds. The check engine warning light was illuminated. The vehicle was taken to the dealer, where it was diagnosed that the PTU had failed and needed to be replaced. The contact stated that the vehicle was repaired under warranty; however, the failure persisted. The contact stated that the vehicle was experiencing hard and erratic transmission shifts, was shuddering, and was making abnormal grinding sounds. The vehicle was taken back to the dealer, where the PTU was replaced a second time under warranty. The contact stated that while driving from the dealer, the 4-Wheel Drive Mode engaged unintendedly. The contact stated that the vehicle remained stuck in 4-Wheel Drive mode and was undrivable. The vehicle was towed to the dealer, where it was determined that the PTU, the transmission, and the drivetrain control module had failed. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was approximately 100,000.