Went to use the car today, started the engine, the aircon indicator light showed that it was in the "econ" mode. I pressed the button to turn the aircon to on, the econ light went out, then after a second or two it came back on again.

If I stop the engine and press the button, the econ light goes off and stays off. If I then start the engine, the econ light comes on after a second or two.

The other heating/ventilating functions seem to work OK.

(Obviously) the aircon is not working, but it was OK yesterday. Does anybody have any idea of the cause.

Geoff