My flashers are only working 50% of the time basically when i really need em they either don't come on or blink once then die but will work 5 minutes later can anyone help me.

Contact GM Customer Service and see if your Alero qualifies for the free flasher replacement. GM issued a TSB on the matter and in effect a recall. Notices were sent out to the original owners or subsequent owners if in their database. I believe the 2003 year should be covered but check just to be sure. All they need is the VIN number.