  The applicability or terminating condition for the ordinary case of
Zeilberger's algorithm was recently obtained by Abramov. For the $q$-analogue,
the question of whether a bivariate $q$-hypergeometric term has a $qZ$-pair
remains open. Le has found a solution to this problem when the given bivariate
$q$-hypergeometric term is a rational function in certain powers of $q$. We
solve the problem for the general case by giving a characterization of
bivariate $q$-hypergeometric terms for which the $q$-analogue of Zeilberger's
algorithm terminates. Moreover, we give an algorithm to determine whether a
bivariate $q$-hypergeometric term has a $qZ$-pair.
