SAN FRANCISCO (CBS SF) — Long-awaited new cars set to debut on Bay Area Rapid Transit this month have failed a key safety inspection and may miss the agency’s Thanksgiving deadline to begin service.

New "Fleet of the Future" BART car being shown in Hayward. (CBS)

New “Fleet of the Future” BART car being shown in Hayward. (CBS)

The California Public Utilities Commission (CPUC) said a 10-car test train using the new cars failed to identify all of them during a test run last Friday and the train operator could not open all the doors.

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BART spokesman Jim Allison said doors did not open on seven of the new cars during the test run, and it’s unclear what cased the problem.

“It’s certainly frustrating because we wanted to get these cars out, serving our passengers sooner,” said Allison. “We know that they’re crowded on old train cars right now, but we simply can’t do it until we’re absolutely sure they’re safe and reliable.”

New BART train interior (CBS)

The CPUC has sent a letter to BART General Manager Grace Crunican saying the agency can’t use the new cars until it corrects the problems and performs another test run.

Allison said BART engineers were working with the train manufacturer, Bombardier, Inc., to identify and correct the problems and it was still possible the first cars may be on the tracks by Thanksgiving.

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“It’s well within the realm of possibility that we’ll get everything in order within the next week or so,” said Allison.

BART received the first new cars in March of 2016 and are at least 16 months behind schedule because of a series of glitches and modifications that had to be made.

New BART train car crashes during test run at Hayward track on April 22, 2016 (CBS).

BART officials are replacing the cars because they are at the end of their 40-year useful life.

The agency is expecting to replace its entire fleet with 775 new cars by 2021.

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