Alfa Romeo 166 – bulbs specification
Type of bulbs
A – All glass bulbs These are pressure-fitted. Pull to remove
B – Bayonet type bulbs Press the bulb, turn counter-clockwise to remove this type of bulb from its holder
C – Tubular bulbs Free them from their contacts to remove
D – Halogen bulbs To remove free it from the clip on its seating
| Bulbs | Figure | Type | Power |
| LOW BEAM/HIGH BEAM (GAS DISCHARGE HEADLIGHTS) | D | D1 | 35W |
| HIGH BEAM HEADLAMP SIGNALLER (GAS DISCHARGE HEADLIGHTS) | D | H1 | 55W |
| LOW BEAM (HALOGEN BULB HEADLIGHTS) | D | H7 | 55W |
| HIGH BEAM (HALOGEN BULB HEADLIGHTS) | D | H7 | 55W |
| FRONT SIDELIGHT | B | H6W | 6W |
| FOG LAMPS | D | H3 | 55W |
| FRONT DIRECTION INDICATORS (COLOURED BULB) | B | PY21W | 21W |
| SIDE DIRECTION INDICATORS | A | 5W Amber | 5W |
| REAR DIRECTION INDICATOR | — | Led | — |
| STOP/SIDE LIGHT | B | 21/5W | 21W/5W |
| REVERSING LIGHT | B | P21W | 21W |
| REAR FOG GUARD | B | P21W | 21W |
| ADDITIONAL STOP LIGHT (3rd STOP) | A | W2.3W | 2,3W |
| REAR SIDE LIGHT (ON BOOT LID) | B | R5W | 5W |
| FRONT ROOF LIGHTS | B | 10W Halogen | 10W |
| BOOT LIGHT | C | 10W | 10W |
| GLOVEBOX AND DOOR LIGHTS | A | W5W | 5W |
| SUN VISOR LIGHT | C | C5W | 5 |
| NUMBER PLATE LIGHT | A | W5W | 5 |
| REAR ROOF LIGHTS | B | HT5W Halogen | 5W |
WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.

