I just picked up a 2001 ML320 and as I was driving home a light came on that reads "BAS
ESP"
What does that mean?

I have no owners manual

It means that you need to have the fault codes read to determine the problem. Brake light switches are the most common problem. Good luck

I had the same thing happen on my 98 ml320. It was the brake switch, an easy DIY job.

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87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)

BAS is "Braking Assist System".
ESP is "Electronic Stability Program"

AS stated that is part of the STANDARD traction system on most 1999 & later Benzes.

Scanning that traction system will shed light on the problem.

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