FiveM sirens not working? Here is why

How native sirens work

A GTA emergency vehicle has:

• Siren bones (siren1 to siren20) on the model, placed where the lamps are, plus glass bones for the lightbar lenses.
• A siren setting in carcols.meta: for each siren slot, its colour, flash sequence, rotation, light and corona.
• A sirenSettings ID in carvariations.meta pointing the model at that setting.

The game flashes each bone’s lamp material and casts light from it according to the setting.

The usual failures

• ID conflict. Two resources define a siren setting with the same ID. Whichever loads last wins, so one car flashes another car’s pattern or nothing at all. Use a unique ID per setting.
• Missing or misplaced bones. Lights that do nothing or glow in the middle of the roof mean the siren bones are missing or not on the lamps.
• The carcols file is not loaded. It needs data_file 'CARCOLS_FILE' in the manifest, listed before the variations file.
• Lamp materials without the emissive setup. The lightbar flashes as a texture but casts no light because the lamp shader or the setting’s light flags are wrong.
• Too many sirens. GTA supports up to 20 siren slots per vehicle.

Native lights without editing files by hand

The Vehicle Editor’s Emergency lights place original GTA lightbars and LED strips on any car, write the siren bones, the lamp materials and a carcols setting with a free ID, and keep the right manifest order. You position the lights on the model, choose colours and a flash pattern, preview the flashing and export.