Traffic lights from Joe Pombo Parkway to Costco were off — not even flashing red — when a midday power failure sapped electricity from the area.
The crash — which police say was probably caused by one or both drivers not stopping properly at the darkened traffic signal — blocked the westbound lanes as crews tended to the injured. A child was trapped in the van but not seriously injured, and three people were taken to San Joaquin County Hospital for their injuries.
Tracy police traffic officers were still trying to figure out who was at fault for the crash Monday afternoon.
Tracy police officers said when a traffic signal is not working the intersection becomes a four-way stop and drivers should be cautious when driving through the area.
Pacific Gas & Electric Co. crews had power back on and the signals working before 1 p.m.