just got this from another source:
The peugeot 306 and 406 suffered strange electrical problems where for instance if a fuse blew on a certain circuit or a failed device caused a short it would cause the battery lamp to light.
For instance i had a 306 hdi in that a customer said he was driving on a motor way with the back wiper on then all of a sudden it stopped mid screen and the battery lamp came on. When i carried out a electrical test i found the rear wiper motor had seized which blew the fuse, i disconnected the motor wiring connector and replace the fuse the battery lamp then went out. I replace the faulty motor it was then sorted. I recon you car is suffering from the same problem as i bet if you remove the blower motor wiring plug and checked the fuse box for a blown fuse you will find your battery light will go out. Once you find this just replace the heater blower motor and you will find all is ok as these commonly fail.
The later 306 and 406 had a can bus electrical system a faulty item will short the circuits
so am iright thinking its the Blower motor ?
theres no squeal from alternator so its not a slipping v-belt alternator is good battery is showing a green light in its bubble on top of battery,
if iturn the blower off and on the battery fault charging warning goes away and reapears a day or so later
