problem in ELM327

[ERAZOR047]

I bought an ELM327(from T-E), and I tested it with two cars (volkswagen golf 3 and citroen xsara) , it shows me information about battery status (12.3v)
and I got this error message :no ECO found

please help me I'm begginer in this domaine , thanks

[Amine-TE]

maybe the ecu is not supported.