instrument cluster illumination not working

[willJspears]

yeah, checked all the fuses, and theyre all good, dont think ive got a rheostat. could a cause of it be the wire going to headlights be earthing on something? only reason i ask is because when i was fitting me boost guage i may have cut the wire casing for the headlight wire where i was jamming a screwdriver through to make some room for the hose? this is the only thing i think it could be.