  Let $\C$ denote the field of complex numbers, and fix a nonzero $q \in \C$
such that $q^4 \ne 1$. Define a $\C$-algebra $\Delta_q$ by generators and
relations in the following way. The generators are $A,B,C$. The relations
assert that each of $A+\frac{qBC-q^{-1}CB}{q^2-q^{-2}}$,
$B+\frac{qCA-q^{-1}AC}{q^2-q^{-2}}$, $C+\frac{qAB-q^{-1}BA}{q^2-q^{-2}}$ is
central in $\Delta_q$. The algebra $\Delta_q$ is called the universal
Askey-Wilson algebra. Let $\Gamma$ denote a distance-regular graph that has
$q$-Racah type. Fix a vertex $x$ of $\Gamma$ and let $T=T(x)$ denote the
corresponding subconstituent algebra. In this paper we discuss a relationship
between $\Delta_q$ and $T$. Assuming that every irreducible $T$-module is thin,
we display a surjective $\C$-algebra homomorphism $\Delta_q \to T$. This gives
a $\Delta_q$ action on the standard module of $T$.
