Twenty days after being pulled offline over equipment concerns, the First Hill Streetcar restarted service Monday morning.

The gold 405 First Hill Streetcar experienced an electromechanical failure around 6 a.m. March 1, causing the vehicle to lose power. Two passengers and the streetcar operator were uninjured when the parking brake engaged, but did not stop the vehicle from sliding 2 1/2 blocks down Broadway Avenue, from Boren to Yesler Way. The track brake was unable to engage while the streetcar was without power.

All First Hill line streetcars were eventually removed from service, as well as one used for the South Lake Union Streetcar, which had been purchased through the same order from Czech manufacturer Inekon.

The malfunction was determined to have been caused by a load contactor — which acts like a circuit breaker — that had tripped into an open position. The load contactor connects the low voltage battery that runs power to the streetcar operations system.

SDOT reports the entire fleet had modifications installed, tested and individually documented.

Andrew Glass Hastings, SDOT transit and mobility director, said all streetcars except for the 405 were returned to service on Monday, March 20, and it won’t be back on the streets until a long-term solution is reached for preventing such power failures in the future.

The short-term solution SDOT, King County Metro and Inekon staff developed wired the track brake to the battery, Glass Hastings said.

“It eliminated the issue we experienced with the power failure, so even in the event of a power failure the track brake would still operate,” he said. “This is kind of our sort of near-term solution to get the vehicles back in service.”

The streetcars will also operate at lower speeds on the two steepest sections of the First Hill line.

“We still have to make sure we do everything we can to make sure the power doesn’t fail,” Glass Hastings said.

The state transportation department and the Federal Transit Authority approved the short-term solutions and plans for next steps to resolve “single-point failure” of the streetcars, Glass Hastings said, and SDOT and King County Metro leadership then approved the resumption of service.

Seattle City Councilmember Rob Johnson had asked during a March 7 Sustainability and Transportation Committee meeting whether the city can seek compensation from Inekon for the cost incurred due to the loss of service.

“Now, as we look to next steps and look forward, we have to answer that question,” Glass Hastings said.

He said part of the warranty with Inekon for the streetcars includes on-site support, which has been used in the past, but never to address an issue this significant.

“They’ve had staff here since the vehicles literally first arrived and were being manufactured,” he said.