  The Boltzmann equation for inelastic Maxwell models is considered in order to
investigate the dynamics of an impurity (or intruder) immersed in a granular
gas driven by a uniform shear flow. The analysis is based on an exact solution
of the Boltzmann equation for a granular binary mixture. It applies for
conditions arbitrarily far from equilibrium (arbitrary values of the shear rate
$a$) and for arbitrary values of the parameters of the mixture (particle masses
$m_i$, mole fractions $x_i$, and coefficients of restitution $\alpha_{ij}$). In
the tracer limit where the mole fraction of the intruder species vanishes, a
non equilibrium phase transition takes place. We thereby identity ordered
phases where the intruder bears a finite contribution to the properties of the
mixture, in a region of parameter space that is worked out in detail. These
findings extend previous results obtained for ordinary Maxwell gases, and
further show that dissipation leads to new ordered phases.
