Chloride channel gated by pH that facilitates the entry of chloride ions into cells upon exposure to extracellular acidic pH (PubMed:31023925, PubMed:31318332). Involved in acidosis-induced cell death by mediating chloride influx and subsequent cell swelling (PubMed:31023925, PubMed:31318332). {ECO:0000269|PubMed:31023925, ECO:0000269|PubMed:31318332}. This is the function of PACC1 (proton activated chloride channel 1, ENSG00000065600).