My check brake light just came on yesterday. Car was driving fine before it came on and still is driving fine. I was wondering if it just needs fluid or if it was something a lot more serious.

Mine did the same thing, it's my center brake light and appearantly the housing can corrode as i changed the bulb and it intermittenly goes on and off. Off to the stealer so they can repair and get a brake job...

hope that helps.

Does the message say "Check Brake Lights" or "Check Brakes"?

I don't remember what the message was when I needed to replace brake pads, but the pad sensor tells the system when your pads are wearing thin. In that case, have them inspected by a mechanic you trust and replace any parts necessary.

If the message says "Check Brake Lights", you have a bulb out. They're easy to get to and cost about $2.00 (max) at NAPA, Auto Zone, etc. Take out the burned bulb to be sure your replacement is the same size and connector.

I'm not sure I've ever seen a dashboard message related to low brake fluid, but I'm sure there is one.

Hope this helps.

I don't know about E39's, but the E34s give false alarms. Mine does it every once in a while, and my lights are fine. I've heard multiple explanations, non OEM bulbs, corrosion, etc. My experience seems to be heat related, and I get the "brake light circuit" warning when it's really hot.

Within the past 2 weeks, I've had 2 warnings to "Check Brake Lights" - neither one a false alarm. I now have new left and center brake light bulbs.

Total cost of repairs: <$5

Total cost of getting in the car after locking keys in trunk outside NAPA: $160+ (new key from stealership)

Had the same thing happening on a 325e, so being a newbie, just got the car at the end of June, I pulled the rear brakes which were nominal(Replaced), did not make problem go away, replaced the bulbs and cleaned all contacts, problem still here, ended up being the stoplight switch that the brake pedal activates, replaced, all is well.