Orange warning light with black fan symbol ?

Hi, An orange warning light appeared on the dashboard of my 04 Citroen Picasso last night, which was followed by a beeping noise. As I'm a member of the RAC I called for their help, they said it would be okay to drive the car as long as the journey was within 50 miles and I keep it to 50 mph max. As I have a return journey of 240 miles in a few days time, this doesn't really help. The RAC won't assist as the car is still driveable and therefore the problem can't be considered a 'breakdown.' Does anyone know what the cause may be. The car sounds the same, oil is fine. If I take it to a garage, I know it will cost at least £80 to get a diagnostic done + the possible repair! Looking on the internet it seems warning lights on Citroen cars are causing havoc for lots of owners, I hope someone out there can shed some light on what the cause may be. Many thanks