Check Brake Lights Warning (and unrelated low coolant warning?)

Started intermittently and has become almost every time I start the car. All brake lights are functional including center light. All bulbs are proper and good condition and I can't find any issue with grounding/melting/otherwise failing housings. Does the e39 suffer from the old pedal sensor failure that other models did? Other thoughts on what could be causing this? Google seems to say not.



Also still got the issue where my cooling system is building up a vacuum/air bubble of sorts if anyone has furher thoughts. Parts are OE, bout three years old, no leaks or loss of fluid, but I get low coolant warnings. Opening expansion tank it appears to be low, but as soon as I open the bleeder screw coolant flows back in and it levels out perfectly.



The joys of a 250k car I guess!

Check Brake Lights Warning (and unrelated low coolant warning?)