Xantia heater

[xud]

The fan will not work on any speed. Why?

[mr rusty]

There are a number of causes and solutions to this, depending which Xantia you have-some related to wiring, others to aircon if you have it.
go here: http://www.frenchcarforum.co.uk/forum/ and do a search on the Citroen forum, where you'll find hours of reading on Xantia heater fans.............post the question there if you can't find the answer by searching.