The camera, at 6523 N. Western Ave., had been sending warnings to speedy motorists for the past 30 days, according to the Chicago Department of Transportation.
But on Tuesday, the city will begin dolling out $35 tickets to those caught going 6 to 10 mph over the posted limit, and $100 for faster than that.
First-time offenders would get a warning.
In August, the city released the 50 locations where speed cameras would be installed by the end of the year.
The Warren Park camera was initially not listed by the city due to an error, said Peter Scales, a Chicago Department of Transportation spokesman.