Fixing Full Brightness That Isn't Working

You installed the pack, but caves are still pitch black. This is almost always a selection or conflict problem, not a broken pack.

Step 1: Confirm It's Selected

Open Options → Resource Packs and check the Selected column. A pack sitting in Available does nothing. Move it right and click Done.

Step 2: Check for Conflicts

Other packs that modify lighting — shader packs, other brightness packs, or packs that replace the lightmap — can override this one. Two fixes:

• Drag Full Brightness above the conflicting pack in the Selected list.
• Temporarily disable the other pack to test.

Step 3: Shaders Override Everything

If you use an external shader loader, its lighting engine replaces the vanilla lightmap entirely, so a resource pack can't brighten the world. Disable shaders to confirm, then either drop shaders or use the shader's own brightness setting.

Step 4: Reload

Press F3 + T to reload resources in-game, or toggle the pack off and on. If a world was loaded before the pack was applied, a reload forces the lightmap to refresh.

If none of this works, the pack version may not match your game version — check that it targets your Minecraft release.