Tests to keep Seattle bus tunnel closed until at least Monday

The downtown Seattle bus tunnel will stay closed until at least Monday, as transit agencies continue to troubleshoot a computer problem in the tunnel's emergency-control network.

The supplier, GE Transportation Systems, has brought in replacement parts, and technicians will conduct tests before any reopening.

"We're taking a holistic look at the entire system," said company spokesman Stephan Koller.

The tunnel, which serves 18 bus routes and 47,000 people each weekday, closed Monday, reopened Tuesday, and closed again Wednesday morning.

The computer problem has tentatively been traced to faulty circuit boards, according to Sound Transit. In an emergency, the ventilation, lights, signals and elevators in five tunnel stations are to be controlled from King County Metro Transit's base in Sodo, but the computer glitch disrupted that link.

Manual controls exist, but more training and perhaps more equipment would be needed to run buses safely through the tunnel that way, transit managers said Wednesday.

Riders can get updates at transit.metrokc.gov or soundtransit.org.