  We investigate the stability of Pexiderized mappings in Banach modules over a
unital Banach algebra. As a consequence, we establish the Hyers--Ulam stability
of the orthogonal Cauchy functional equation of Pexider type
$f_1(x+y)=f_2(x)+f_3(y)$, $x\perp y$ in which $\perp$ is the orthogonality in
the sense of Ratz.
