The function of KCNG3 (potassium voltage-gated channel modifier subfamily G member 3, ENSG00000171126) is as follows. Regulatory subunit of the voltage-gated potassium (Kv) channel which, when coassembled with KCNB1, modulates the kinetics parameters of the heterotetrameric channel namely the inactivation and deactivation rate (PubMed:11852086, PubMed:12060745, PubMed:19074135). Potassium channel subunit that does not form functional channels by itself (PubMed:11852086, PubMed:12060745). Reduces the deactivation rate (PubMed:11852086). Moderately accelerates activation (PubMed:12060745). {ECO:0000269|PubMed:11852086, ECO:0000269|PubMed:12060745, ECO:0000269|PubMed:19074135}.