Weapon mods

Do weapon mods take effect regardless of whether you use that weapon in a fight?

For example, if I have Tactical Illuminator (-5.00 Opponent Accuracy, -3 Opponent Stealth) equipped on my rifle but have my attack settings 100% melee.
Do I still get the effect or does it only activate when I fire the rifle?

TIA

It works the turn that you used the weapon

The mods only affects the weapon it is equipped with it.

For defends I recommend toggling no reload and leaving melee at 1%, so when you run out of clip ammo you will use your melee weapon (unless ofc you have an OP melee like the umbrella)