The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  2  0  0  0  2  0 2a 2a  2 2a+2 2a+2  2  0  0
 0  0  2  0  0 2a+2  2  0 2a 2a 2a  2 2a  0  2
 0  0  0  2  0  2 2a+2 2a+2 2a  0 2a  2  0 2a+2 2a
 0  0  0  0  2 2a+2 2a  2 2a+2  2  0  2 2a+2 2a+2 2a+2

generates a code of length 15 over GR(16,4) who´s minimum homogenous weight is 32.

Homogenous weight enumerator: w(x)=1x^0+42x^32+123x^36+189x^40+195x^44+3072x^45+225x^48+153x^52+87x^56+9x^60

The gray image is a code over GF(4) with n=60, k=6 and d=32.
This code was found by Heurico 1.16 in 0.0246 seconds.