  We establish pointwise bounds for the Green function and consequent
linearized stability for multidimensional planar relaxation shocks of general
relaxation systems whose equilibrium model is scalar, under the necessary
assumption of spectral stability. Moreover, we obtain nonlinear $L^{2}$
asymptotic behavior/sharp decay rate of perturbed weak shocks of general
simultaneously symmetrizable relaxation systems, under small $L^{1}\cap
H^{[d/2]+3}$ perturbations with first moment in the normal direction to the
front.
