TriMet is investigating what caused one of its doors on a MAX train to stay open while the train was moving at full speed.
The clip shows the train traveling at highway speeds, with traffic running parallel to the train and the door wide open.
"Open door on the MAX while riding, open door on the MAX while riding," the man recording the video is heard saying.
At one point, someone tugs at a door in an attempt to close it, to no avail. Later, a man walks over to the open doors and leans out a few times before returning to a seat.
The doors eventually close as the train approaches the Lloyd Center station.
The incident happened shortly after 1 p.m. Friday as the train left the Hollywood Transit Center.
"I saw two people try to catch the MAX before it leaves. They grab the door, grab it. The doors open. Jams," said Chadd Thayer, who was at the Hollywood Transit Center
He alerted TriMet to the problem using his Twitter account.
A TriMet spokeswoman released a statement after video of the open door was posted on YouTube.
"Once the operator was alerted to the malfunction, the door was immediately disabled," according to TriMet. "This type of failure is rare and the train has been pulled from service as crews investigate. We always encourage the public to immediately alert the operator if they see any safety concern."
"This is something that's absolutely not supposed to happen. There are a number safeguards that are built into the car," said Harry Saporta, TriMet safety and security executive.
Saporta said MAX trains have a system called a door summary circuit, which is supposed to prevent the trains from moving while the doors are open.
"There are a series of relays that are designed so that if the doors are in the open state, it does not allow the car to move," he said. "In this particular case, there was a malfunction, we're trying to figure out exactly what happened."
TriMet is also looking into how and when the driver was notified of the open doors.
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