The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  2  1  1  1  2  1  1
 0  2  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  2  2  2  0  2  2
 0  0  2  0  0  0  0  0  0  0  0  0  0  0  0  0  2  2  2  2  2  2  2  0
 0  0  0  2  0  0  0  0  0  0  0  0  0  0  0  2  0  2  0  0  2  2  0  2
 0  0  0  0  2  0  0  0  0  0  0  0  0  0  2  2  2  0  0  0  2  2  0  0
 0  0  0  0  0  2  0  0  0  0  0  0  0  0  2  0  0  2  0  2  0  2  0  2
 0  0  0  0  0  0  2  0  0  0  0  0  0  0  2  2  2  2  2  0  2  0  2  0
 0  0  0  0  0  0  0  2  0  0  0  0  0  2  2  2  0  0  2  2  0  0  0  2
 0  0  0  0  0  0  0  0  2  0  0  0  0  2  0  0  0  2  0  0  2  2  2  0
 0  0  0  0  0  0  0  0  0  2  0  0  0  2  0  2  2  2  0  2  0  2  0  0
 0  0  0  0  0  0  0  0  0  0  2  0  0  2  0  2  2  0  2  0  2  0  0  2
 0  0  0  0  0  0  0  0  0  0  0  2  0  2  2  0  2  0  0  2  0  2  2  2
 0  0  0  0  0  0  0  0  0  0  0  0  2  2  2  0  2  2  2  2  0  0  2  0

generates a code of length 24 over Z4 who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+93x^12+240x^14+322x^16+512x^18+952x^20+3440x^22+5440x^24+3136x^26+954x^28+656x^30+373x^32+192x^34+48x^36+16x^38+8x^40+1x^44

The gray image is a code over GF(2) with n=48, k=14 and d=12.
This code was found by Heurico 1.16 in 6.77 seconds.