The car is an 06 plate CDTI 2.2 L diesel. Owned for 8 years. A month ago the alternator was replaced because of a mechanical issue. The new alternator was fine but now the battery light is flashing on for a few seconds. That has happened several times during local trips. I have run with all electrical items on but still only intermittant and short period when the light comes on. I need to do a 400 mile trip and worried about reliability. The battery indicates fully charged but has never been replaced by myself. The engine starts immediately from cold. Any ideas or suggestions would assist.