Last week, while driving my 02 C4S, the check battery/charging system light came on. No problems with driving. The voltage seemed to stay steady at around 13V. The car starts fine, but the light remains on constantly. I just changed the battery about 6 months ago. Any ideas? I don't have time to take it in this week, but will probably bring it in to my mechanic next week.
Thanks in advance for any input!

 

Loose alternator belt? The ignition switch is a common source of electrical glitches - they get worn. Cheap fix on that, though.