A failed modem is being blamed for another major disruption of the SkyTrain system Tuesday evening.
Delays began on the Expo and Millennium lines after 6 p.m., causing heavy backups at several stations.
Trains weren't running between Nanaimo and Joyce stations but up to 22 buses were used to shuttle passengers around that section until trains began running normally there at 9:45.
TransLink officials said the modem was in a computer that controlled 10 track switches for Edmonds and Joyce stations. The failed device, which communicates between field devices and central control, was less than a year old and still under warranty.
The failure was the fourth significant delay for SkyTrain passengers in recent months. Two major shutdowns within a week in July triggered an independent review, which is to report back at the end of October.
The July shutdowns were prolonged because some passengers forced open SkyTrain doors and walked out along the guideway.
On Tuesday, TransLink detected the hardware failure in time to move nearly all trains into the stations, so no trains were stuck mid-way between stations on the guideways.
"That made a big difference," spokesperson Cheryl Ziola said. "We were really fortunate this time."
She said staff also gave passengers frequent updates via loudspeaker, Twitter and in-station TV monitors.
"These delays are no different than those experienced by any other transit agency around the globe," Ziola said, adding a New York transit line was recently shut down because two kittens were on the track.