I have a 2002 Impala and the signal flasher quits

Your turn signal and hazard flasher assembly is one unit,it is part of your Big hazard button,this was a very common problem with GM they used this same thing in alot of there models with a high failure rate,You have to gain access to the back inside the dash and depress a plastic tab and the assembly pushes out towards you I usually remove dash face and then pull the radio out a little to gain access,the dash face is in with push retainers pull off very carefully,then remove radio but don't disconnect wires just pull out enough to gain access.