From the Downtown Yonge BIA website it's lights.
Street Lighting Construction:
HOURS OF WORK: Weekdays (M-F) from 7am to 7pm;
2 lane closure in the area of construction from 7am – 7pm;
Curblane Closure weekdays (M-F only/ 24/7);
No work or lane closures during weekends (Sat/ Sun).
West Side of Yonge: from Dundas to Shuter Street
Construction will start this week on the West side of Yonge Street at Dundas, and working from north to south, crews will undertake civil work (excavation and structural footing installation) over the course of the next 6 weeks (mid Aug).
East Side of Yonge: from Shuter Street to Dundas
Construction will start in mid August on the East side of Yonge at Shuter Street, and working from south to north, crews will undertake civil work (excavation and structural footing installation) over from approx. mid August to late September.