NAM

After two years of struggling to find the answer with my Xantia Estate (yr 2000) I took the car to main dealer who eventually traced the fault to the ECU. They replaced the original and all works fine - the light is no more! I had done the under seat bit and tried to have codes read but as the ECU was not working no-one could read the codes. Cost me just under £300 but I felt I had to get this fault fixed. Hope you can sort yours for less.

I have the same problem and have had diagnostics read with no luck. The options seem to be main dealer (check the cost for them reading the diagnostics first) or replacing the ECU. There is quite of bit of suggestion about the wiring under the seats being stretched and it should be checked but if you have done this I suggest having the codes read. If you find the answer please let me know!

Have you checked to see if water is coming in at the rear of the boot area (where the tailgate shuts?). I have an estate and had a problem with water in the back of the car which ended up wetting the seat well. My local Citroen specialist repacked the tailgate mechanism and fixed the problem - not sure exactly what they did but only charged £50 and after months of wet carpets seemed money well spent. I rang them and they knew straight away what the problem was. Hope you can get it sorted. NAM