Enzyme complex consisting of four proteins: the two subunits of the hydroxylase component (hcaE and hcaF), a ferredoxin (hcaC) and a ferredoxin reductase (hcaD). Converts 3-phenylpropionic acid (PP) into cis-3-(3-carboxyethyl)-3,5-cyclohexadiene-1,2-diol (PP-dihydrodiol).