There's a problem with the wiring harness that's causing the issue.
Automotive supplier ZF will recall 505,000 nine-speed automatic gearboxes that can shift into neutral without warning. According to the company’s report to the National Highway Traffic Safety Administration, the problem is due to "insufficient crimps” in the wiring harness for the Transmission Control Sensor Clusters. The component helps control the shift pattern, and the affected parts have production dates between May 1, 2013, and July 15, 2014.
ZF received the first report of this issue in July 2004 when a supplier reported a single failure during transmission testing. At the end of 2015, Fiat Chrysler Automobiles told the supplier about an increased number of field reports about this problem. ZF analyzed the issue and began developing upgraded software.
The fault specifically affects the company’s model 9HP48 or 948TE gearboxes. These transmissions appear vehicles from Honda, FCA, and Land Rover, including recent models like the latest Chrysler Pacifica.
As the product’s supplier, ZF will first contact the automakers with these transmission in their vehicles. The companies will then issue separate recalls about the problem, they’ll also contact owners. Dealers will install updated software that will “prevent the transmission from shifting into neutral due to a faulty crimp.”