The generator matrix

 1  1  1  1  1  1  1  X  X  1  1  2  1  1  1
 0  X  0  X 2X  0 X+2 2X+2 3X+2 3X 2X  X 3X X+2  2
 0  0  X  X  2 X+2  X  X 2X  2 X+2  X  2 3X+2 2X+2
 0  0  0  2  0 2X  2 2X+2  2 2X  2 2X  2 2X 2X

generates a code of length 15 over Z4[X]/(X^2+2) who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+317x^12+96x^13+1080x^14+1088x^15+1146x^16+96x^17+232x^18+39x^20+1x^24

The gray image is a code over GF(2) with n=120, k=12 and d=48.
This code was found by Heurico 1.16 in 13.9 seconds.