Can't read codes
 

I have an 04 E55 for which I can't read the codes using my pocket ODBII scanner. Also, the indy shop that I take it to (they are a MB specialty shop) has the same problem. They tell me that for some reason, they can't communicate with the ecu on my car to pull the "check engine" codes. I'm not sure what they are using but I am assuming it is an MB tool if not the STAR diag system. I had a check engine light on and they had to take it to the dealer to get it reset.

I know ODBII is a standard and all readers should be able to pull the codes.
Anybody have any thoughts? What could be wrong?

i had CEL once and cleared with my OBDII reader... :nix:

Yeah, it's supposed to work..I am trying to figure what might cause it to not work and what the tell the dealer to fix.

Thanks for the reply!