Why is it you are replacing it? Is it because you see that warning sign when
you just started up the car first thing in the morning? And that sometime it
doesn't show up?

I'd suggest you look over your service record and see when you replaced your
main battery.... The reason I asked is that my folk's 01 E320 did the same
thing... will always show up first thing in morning and randomly all other
time. We had the dealer check and nothing is wrong with it. On the second
time, they did an extensive test and found the main battery is bad... that
causes that malfunction error.

Voltage is very important for computer... it is how they determine if
something is wrong... so weak battery will show lower sensor reading and
computer may thing something is bad.

The car starts with zero problem but we get lots of errors... ABS, BAS and
finally SRS... geez... All fixed with a new battery.