Well, its a warning light whose purpose is to tell you that your brake fluid level or brake pads might need attention... Thats the first thing to think. Flickering under acceleration suggests it is related to the fluid sloshing around. Further thinking can lead to the conclusion that one reason that the level is down(if it is) could be because the pads are worn down, so the pistons are pushed out of the calipers, so lowering the level in the reservoir. So don't top up the reservoir in that case until you have checked the pads or else when the pistons are pushed in to make way for new pads, the reservoir will overflow, spilling fluid on the bodywork, dissolving the paint. This causes dissatisfaction.
Of course, if you find evidence of a leak (such as suggested in above posts) then you have a leak instead.
Last edited by SimonT; 25-10-12 at 21:29.