What it is
The Authorisation Response Code (ARC) is the 2-character result returned by the issuer (or generated by the terminal for offline decisions). The card inspects it in the second GENERATE ACApplication CryptogramA cryptogram the card generates to approve or decline a transaction: TC (approve offline), ARQC (go online), or AAC (decline). to decide the final cryptogram. "00" and "Y1/Y3/Z1/Z3" style values indicate approval or offline decisions.
Where it appears
Provided to the card in CDOL2 data for the second GENERATE ACApplication CryptogramA cryptogram the card generates to approve or decline a transaction: TC (approve offline), ARQC (go online), or AAC (decline)., after the online response.
Specification reference
Defined in: EMV 4.x Book 3 (Application Specification), Annex A — Data Element Dictionary
Example values
3030"00" — approved
5A31"Z1" — offline decline