BOISE, Idaho (AP) — The Ada County Highway District is abandoning an adaptive traffic light program that was supposed to reduce congestion at busy intersections, saying it caused more problems than it fixed.

KTVB-TV reports that ACHD spokeswoman Nicole DuBois says the sun glare, fog and other problems stopped the mounted cameras from accurately counting how many cars were stopped at a light. The system was supposed to give green lights to cars when there was no traffic coming, but the inaccurate counts stopped that from happening.

DuBois says drivers were also inconvenienced by the constant work trying to fix the system. The sensors purchased from Rhythym Engineering last year cost $600,000. DuBois says the district is negotiating to get that money back.