The $650-million, 3.8-mile-long elevated dual-lane fixed-guideway was to begin service on Jan. 20, carrying 8,000 passengers hourly between the city’s convention center and eight resorts. But the date was postponed after a driveshaft fell off a Bombardier train during a test run. Technicians then experienced computer problems with the automated guidance system that have since been fixed.

The line must operate at 98% of its intended capability for 30 days before it can carry passengers, says a spokesman for Las Vegas Monorail Co., the project’s private for-profit owner. Service is now expected to begin this summer, he adds.