blinker/ flasher do not work on 2004 Chevrolet Impala

The turn signal or hazard warning do not flash. All bulbs check o.k.

Asked by for the 2004 Chevrolet Impala
If the bulbs and fuses all check ok then I would suspect a faulty hazard switch. The hazard switch also controls the "flashing" of both the turn signals and the hazard lights. Try turning on and off the hazard switch a few times to see if you can get the lights to start working again.
1 more answer
Russ is right its probably the hazard switch its available at put in your year make and model then put hazard in the search box about $50 plus shipping