Calcium-dependent membrane association of a flagellar calcium sensor does not require calcium binding

•FCaBP is a flagellar calcium sensor of Trypanosoma cruzi that displays calcium-dependent membrane association.•An FCaBP mutant that does not bind calcium still shows calcium-dependent membrane association.•FCaBP can form dimers, so the FCaBP calcium-binding mutant is still flagellar because it can dimerize with resident FCaBP.