Immune activating receptor involved in self-nonself discrimination. In complex with KLRD1 on cytotoxic lymphocyte subsets, recognizes non-classical major histocompatibility (MHC) class Ib HLA-E loaded with signal sequence-derived peptides from non-classical MHC class Ib HLA-G molecules, likely playing a role in the generation and effector functions of adaptive natural killer (NK) cells and in maternal-fetal tolerance during pregnancy (PubMed:30134159, PubMed:37264229, PubMed:9754572). Regulates the effector functions of terminally differentiated cytotoxic lymphocyte subsets, and in particular may play a role in adaptive NK cell response to viral infection (PubMed:20952657, PubMed:21825173). Upon HLA-E-peptide binding, transmits intracellular signals via the adapter protein TYROBP/DAP12, triggering the phosphorylation of proximal signaling molecules and cell activation (PubMed:15940674, PubMed:9655483). {ECO:0000269|PubMed:15940674, ECO:0000269|PubMed:20952657, ECO:0000269|PubMed:21825173, ECO:0000269|PubMed:30134159, ECO:0000269|PubMed:37264229, ECO:0000269|PubMed:9655483, ECO:0000269|PubMed:9754572}. This is the function of Ensembl gene identifier ENSG00000205809 (KLRC2, killer cell lectin like receptor C2).