Tank7

Was driving down an hill and gently braked to reduce speed (Escort went off) when the BAS/ESP lamp lit up and stayed on. Got to destination, parked. Shut off engine, restarted engine and the lamp no longer stayed on.

Did NOT do the Left Right Hoky Poky with shutdown, nor has it come back on again.

Does this need to be checked regardless?

MBZFAN55

I had the same problem on my 2000 S430 where the message appeared as a "malfunction". The problem occured intermittantly and was usually corrected with a "restart", as were other electronic issues with the car. The dealer gave me some convoluted story that the message was being caused in error due to light and or heat travelling up the steering column. The problem continued to occur for about a year and then coincidentally stopped entirely during one of my many electronics oriented service dept. visits.

trbo2nr

This has happened to me too. I did the left right thing you mentioned and it took care of it. I wouldn't worry about it unless it never goes off.

Spriro

If it comes back again, most likely you have to change the brake light switch.
You can drive it okay while it is on but your cruise control will be malfunction.
And it is really annoying looking at that BAS/ESP warning while you are driving. :p