Ive had this warning light for some time now, I've just swapped out the brake fluid reservoir and bled all the brakes and that didn't cure the problem, has anyone else had this issue ? obviously the brake fluid isn't low.

 

The fluid reservoir has a fluid-level indicator switch which normally operates when the fluid level is low, illuminating the brake fluid level warning-lamp.



If the sensor is faulty it will either fail ON permanently or OFF permanently. Less likely is a break in the harness but the connector could be loose.

Graham