Brake fluid level warning light

[sunbeam alpine]

My mate has bought a cheap car for his daughter to learn on. MOT gave an advisory for brakes, so we've replaced them this weekend. We also renewed the brake fluid.

Since we've done this the warning light for the brake fluid level comes on when the car is started (it also gives a beep). The car drives and brakes fine - I've got a pressure bleed system which makes the job very easy - and the master cylinder is full. It's maybe even a bit too full - it's definitely over max.

My question is - would a high level also cause the warning light to come on? Google is not currently being my friend on this!

Car is a Citroen Xsara if that helps.

[sunbeam alpine]

Wow. Thought it was strange that I hadn't had any replies. Now see the thread's been moved.

Shall I do some dusting/remove the cobwebs while I'm here?

[daimatt]

Worth syringing some out. I had a car where the rubber diaphragm distorted when I replaced the cap and this caused the light to come on so maybe have a look around the whole reservoir area, where the sensor is etc.