The technology, known as positive train control, or PTC, was not installed on the Amtrak train that derailed last year south of Tacoma, killing three people and injured dozens.
The Daily News of Longview reports that state officials say service on the Point Defiance Bypass route will resume in the spring. The state said PTC testing and crew training will occur on that route throughout fall and winter.
The National Transportation Safety Board is investigating the Dec. 18, 2017, wreck.
The Amtrak train was recorded at 78 mph (125 kph) as it rounded a curve in a 30-mph (48 kph) zone, and plunged off a highway overpass near DuPont and onto busy Interstate 5.