Fault codes stored?

[DaveH_Rhyl]

Just had an inspection done on a '08 C class 180 Kompressor 2dr auto I was thinking of buying.
Multiple fault codes appeared on the mechanic's scanner (I couldn't be there myself).
C1024
C1210
C1162

And many others.

When I decided not to buy the vehicle (there were other issues too), I mentioned the codes to the dealer, after telling him that the mechanic had cleared the codes, done a test drive, rescanned and the codes were still there.
He claimed that Mercedes fault codes are stored permanently, and cannot be 'deleted' from the system.
Is he telling the truth or full of it?

 

[Botus]

that's an interesting point....

there does seem to be two areas codes get stored.... but few seem to know

if your tool is looking at the normal code list and the fault is old, it should clear and stay gone.
I suspect in developer mode there is a second fault list that's intended to be permanent.... and you shouldn't find it with normal diagnostic scanning.

My autel kit finds BOTH and it does my head in. But if the fault is cured the user list clears and only "previous faults" that once occurred still show up...
the silly thing is this other list remains but its full of junk - as any programming can disconnect a module from the network and throw ALL possible codes in to the mix - and thus it OUGHT to be cleared after updates are completed.

I have an old memory card with the pervious database that's "NORMAL" and only shows the current stuff, and then another with the current autel stuff for Mercs that shows BOTH, with many that aren't real and I can't clear them (with the majority only ever coming in to play from programming work on SAMs and GATEWAYS)