What to Know
The cars were removed overnight after Metro received a report of a door malfunction
The cause of the malfunction has been determined, Metro said
The removals reduced the number of available rail cars by about 15%
Metro is putting hundreds of cars back into service Wednesday after investigating reports that a door malfunctioned.
The 3000-series cars were cleared to get back on the tracks about one day after being pulled.
Officials launched an investigation after a train left the Dunn-Loring station in Northern Virginia without all its doors closed. Metro says the train operator didn't know the door was open as the train moved because electrical equipment wasn't working properly.
A "master control" problem caused the failure, Metro officials said at a news conference Wednesday. Twenty-six other rail cars could have had the issue, but the root cause has been fixed, Metro says.
All 2000- and 3000-series trains were inspected and deemed safe, Metro says.
No further service interruptions are expected. WMATA says they will release more details on the cause later.
About 15% of Metro's fleet is made up of 3000-series cars, prompting Metro to send fewer eight-car trains.
According to WAMU, a video depicting the open door was shared on a local Facebook page.
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