The generator matrix

 1  0  0  1  1  1 3X  1  1  1  0 X+2  1 2X+2  X
 0  1  0  2  1 3X+1  1  2 X+2  3  1  1 X+3 2X X+2
 0  0  1 X+3  1  2  3  X  3 X+2 X+1  0 X+3  1 2X+2
 0  0  0 2X 2X 2X  0  0  0  0 2X 2X  0  0 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+304x^12+808x^13+1874x^14+2248x^15+1883x^16+760x^17+268x^18+24x^19+20x^20+2x^22

The gray image is a code over GF(2) with n=120, k=13 and d=48.
This code was found by Heurico 1.16 in 0.109 seconds.