I don't know if the zero uses the same parameter numbering scheme, but I have a manual for a Fanuc PowerMate H, and for it, the value in parameter 3102 determines the display language.
0 = English
1 = Japanese
2 = German
4 = French
16 = Italian
32 = Spanish
The display may show bits rather than a numeric value. It might also show abbreviations for the language associated with each bit. The manual gives:
Bit 0 - JPN
Bit 1 - OGRM
Bit 2 - OFRN
Bit 4 - OITA
Bit 6 - OSPN
You could look at the parameter values, and if you find the the current value for 3102 is 2 (Bit 1 set), try changing it to zero and see what happens.
According to the manual you need to cycle power following a change in the value. Of course, you will need to set the PWE bit before you can make the change.
Hope this helps