ML 320 has oil hi light come on. Checked oil level and it does look high. How can this happen and what should I check or do?

would be something in the crankcase in addition to oil, such as coolant. You should drain the oil right away and see if it looks normal.

Should be checked a few minutes after turning engine off.

If its overfilled, someone overfilled it or its leaking coolant which should be obvious after looking at the condition of the oil.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

its not always real obvious if you have coolant in there .. depends on how old your oil is, what kind, and how much coolant is actually in there if any at all ..