If it is the alternator or not, the fact is that my father in law's C3 stop
functioning for four times now (in six months) and the first two times they
swaped the battery, and the second time they swapped "an electrical
component"... Also the power steering stop functioning.
The forth time it was rigth yesterday so I don't know what will be the
solution. I think he will ty to get a new car back or even the money back!
I advised him to buy an YARIS, but he's a Citroen fan...
There is at least another topic on this forum regarding electrical
problems on C3.
Best regards and best of luck.