This page lists 111 electrical bulb & socket parts for the 2003 Alfa Romeo 166, across 16 part types, covering the 3.0L V6 engine. Every part shows its brand, manufacturer part number and fitment notes.
On the 2003 Alfa Romeo 166, the bulb and socket system covers every bulb and socket on the vehicle, from headlamps to instrument-cluster illumination. Most of the listed parts are Fog / Driving Lamp Bulb (16 parts), Headlamp Bulb (16 parts) and Side Marker Light Bulb (11 parts). The other 13 part types cover the remaining 68 parts.
The 2003 Alfa Romeo 166 came with a single engine, the 3.0L V6, and every part is verified against it.
4 brands supply electrical bulb & socket parts for the 2003 Alfa Romeo 166, led by SYLVANIA (61 parts), WAGNER (30 parts) and PHILIPS (18 parts), plus 1 more brand. Quality grades include Standard Replacement, Extra Bright and Extended Life.
A "Popular" badge means the source catalog flagged the part as frequently chosen for the 2003 Alfa Romeo 166. 25 parts have it, including SYLVANIA 7506LL (Back Up / Reverse Lamp Bulb) and SYLVANIA 7443LL (Brake Light Bulb). Each part number opens a page with every vehicle that part fits.
Back Up / Reverse Lamp Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7506LL | 🇲🇽 MX | Long LifeBase Type: BA15S | View on Amazon |
| WAGNER Popular | 17635LL | 🇲🇽 MX | Long LifeBA15S Base | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 7506ST | 🇲🇽 MX | Cool WhiteSilver Star | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 7506 | 🇲🇽 MX | Base Type: BA15SWattage: 25.00 W | View on Amazon |
| WAGNER | 17635 | 🇲🇽 MX | BA15S Base21.000 Watt | View on Amazon |
| WAGNER | 7506L | 🇲🇽 MX | Long LifeBulb Type: T-6 Bulb 3/4 (19mm) Diameter | View on Amazon |
This table covers the bulbs in the reverse lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
6 Back Up / Reverse Lamp Bulb parts for the 2003 Alfa Romeo 166 come from 2 brands — SYLVANIA and WAGNER. The "Popular" part is SYLVANIA 7506LL.
In the Extended Life grade, SYLVANIA and WAGNER supply 2 parts: grouped under the catalog's "Extended Life" designation — the notes column spells out what sets them apart. A representative part number is SYLVANIA 7506LL.
In the Extra Bright (improved visibility, but shorter life) grade, SYLVANIA supplies 1 part: grouped under the catalog's "Extra Bright (improved visibility, but shorter life)" designation — the notes column spells out what sets them apart. A representative part number is SYLVANIA 7506ST.
In the Standard Replacement grade, WAGNER and SYLVANIA supply 3 parts: built to original-equipment specification. A representative part number is SYLVANIA 7506.
This group includes SYLVANIA 7506LL, WAGNER 17635LL and SYLVANIA 7506ST and the remaining parts above.
Brake Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7443LL | 🇲🇽 MX | Base Type: W3X16QLong Life | View on Amazon |
| WAGNER | 7528LL | 🇲🇽 MX | Long LifeGlass:Clear (S8), Number of Filaments:2, Watts:21/5, Base:Bayonet (BAY15D) | View on Amazon |
| WAGNER | 17916LL | 🇲🇽 MX | Long LifeBAY15D Base | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 7443ST | 🇲🇽 MX | Cool WhiteSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | 7443LED | 🇲🇽 MX | VisionLED | View on Amazon |
| SYLVANIA | 7443RSL | 🇲🇽 MX | LED | View on Amazon |
| SYLVANIA | 7443RLED | 🇲🇽 MX | ZEVO | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7443 | 🇲🇽 MX | Base Type: W3X16QWattage: 5.30 W | View on Amazon |
| WAGNER | 17916 | 🇲🇽 MX | BAY15D Base21.000 Watt | View on Amazon |
This table covers the bulbs in the stop lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
9 Brake Light Bulb parts for the 2003 Alfa Romeo 166 come from 3 brands — SYLVANIA, WAGNER and PHILIPS. The "Popular" part is SYLVANIA 7443LL.
Extended Life: 3 parts, from WAGNER and SYLVANIA. A representative part number is SYLVANIA 7443LL.
Extra Bright (improved visibility, but shorter life): 1 part, from SYLVANIA. A representative part number is SYLVANIA 7443ST.
The LED (instant-on, long life, energy-saving) section lists 3 options from SYLVANIA and PHILIPS — grouped under the catalog's "LED (instant-on, long life, energy-saving)" designation — the notes column spells out what sets them apart. PHILIPS 7443LED is listed in this group.
Standard Replacement: 2 parts, from SYLVANIA and WAGNER. A representative part number is SYLVANIA 7443.
Listed part numbers: SYLVANIA 7443LL, WAGNER 7528LL and WAGNER 17916LL, plus the other parts above.
Brake Light Bulb - High Mount
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | 12505LL | 🇲🇽 MX | Longer Life | View on Amazon |
| SYLVANIA | 2723LL | 🇲🇽 MX | Base Type: T1 1/2Long Life | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2723 | 🇲🇽 MX | View on Amazon |
This table covers the bulbs in the high-mount stop lamp. Typical signs include a clunk on takeoff, a vibration at idle, or a separated rubber insert. Support the powertrain before unbolting a mount, and torque the fasteners in the notes.
3 Brake Light Bulb - High Mount parts for the 2003 Alfa Romeo 166 come from 2 brands — SYLVANIA and PHILIPS.
Extended Life: 2 parts, from PHILIPS and SYLVANIA. A representative part number is PHILIPS 12505LL.
Standard Replacement: 1 part, from SYLVANIA. A representative part number is SYLVANIA 2723.
This group includes PHILIPS 12505LL, SYLVANIA 2723LL and SYLVANIA 2723.
Daytime Running Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | H1LL | 🇲🇽 MX | Long Life | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | H1PR | 🇲🇽 MX | Vision30% More Light | View on Amazon |
| PHILIPS | H1VP | 🇲🇽 MX | Vision Plus60% More Light | View on Amazon |
| PHILIPS | H1CVP | 🇲🇽 MX | Crystal Vision PlatinumUp to 60% More Light | View on Amazon |
| SYLVANIA | H1XV | 🇲🇽 MX | Xtra VisionColor Temperature: 3200 KV | View on Amazon |
| SYLVANIA | H1ST | 🇲🇽 MX | Color Temperature: 4000 KVSilver Star | View on Amazon |
| SYLVANIA | H1SU | 🇲🇽 MX | Silver Star UltraColor Temperature: 4100 KV | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS Popular | H1 | 🇲🇽 MX | View on Amazon | |
| SYLVANIA Popular | H1 | 🇲🇽 MX | Base Type: P14.5sWattage: 55.00 W | View on Amazon |
This table covers the bulbs used as daytime running lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
9 Daytime Running Light Bulb parts are listed for the 2003 Alfa Romeo 166, from SYLVANIA and PHILIPS. PHILIPS H1 carries the "Popular" badge.
The Extended Life section: 1 option from SYLVANIA. SYLVANIA H1LL is listed in this group.
The Extra Bright (improved visibility, but shorter life) section: 6 options from PHILIPS and SYLVANIA. PHILIPS H1PR is listed in this group.
The Standard Replacement section: 2 options from PHILIPS and SYLVANIA. PHILIPS H1 is listed in this group.
Listed part numbers: PHILIPS H1, SYLVANIA H1LL and PHILIPS H1PR, plus the other parts above.
Door Panel Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825LL | 🇲🇽 MX | Long LifeBase Type: W2.1x9.5d | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825ST | 🇲🇽 MX | BlueSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825SL | 🇲🇽 MX | LEDCool White | View on Amazon |
| SYLVANIA | 2825BLED | 🇲🇽 MX | ZEVO | View on Amazon |
| SYLVANIA | 2825BSL | 🇲🇽 MX | LED | View on Amazon |
| SYLVANIA | 2825LED | 🇲🇽 MX | ZEVOCool White | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825 | 🇲🇽 MX | Base Type: W2.1x9.5dWattage: 5.00 W | View on Amazon |
This table covers the replacement bulbs for the Door Panel Light. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
SYLVANIA supplies the 7 Door Panel Light Bulb parts for the 2003 Alfa Romeo 166. SYLVANIA 2825LL carries the "Popular" badge.
The Extended Life section: 1 option from SYLVANIA. SYLVANIA 2825LL is listed in this group.
The Extra Bright (improved visibility, but shorter life) section: 1 option from SYLVANIA. SYLVANIA 2825ST is listed in this group.
LED (instant-on, long life, energy-saving): 4 parts, from SYLVANIA. A representative part number is SYLVANIA 2825SL.
The Standard Replacement section: 1 option from SYLVANIA. SYLVANIA 2825 is listed in this group.
Part numbers include SYLVANIA 2825LL, SYLVANIA 2825ST and SYLVANIA 2825SL, among others listed above.
Fog / Driving Lamp Bulb
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WAGNER Popular | H3BLX | 🇲🇽 MX | BritelitePK22S Base | View on Amazon |
| PHILIPS | H3PR | 🇲🇽 MX | Vision30% More Light | View on Amazon |
| PHILIPS | H3CV | 🇲🇽 MX | Crystal Vision UltraBright White Xenon-Look | View on Amazon |
| PHILIPS | H3CVP | 🇲🇽 MX | Crystal Vision PlatinumUp to 60% More Light | View on Amazon |
| SYLVANIA | H3ST | 🇲🇽 MX | Silver StarColor Temperature: 4000 KV | View on Amazon |
| WAGNER | H3TVX | 🇲🇽 MX | Truview PlusPK22S Base | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | H3USLED | 🇲🇽 MX | Ultinon Sport LED | View on Amazon |
| WAGNER | H3LED | 🇲🇽 MX | LED | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS Popular | H3 | 🇲🇽 MX | Front | View on Amazon |
| SYLVANIA Popular | H3 | 🇲🇽 MX | Base Type: PK22Wattage: 55.00 W | View on Amazon |
| WAGNER Popular | 1255H3 | 🇲🇽 MX | FrontHalogen Capsule | View on Amazon |
| WAGNER | 1210H3 | 🇲🇽 MX | Glass:Clear (T3-1/2),# of Filaments:1,Watts:55,Base:Pigtail (PK22S) | View on Amazon |
| WAGNER | 2470H3 | 🇲🇽 MX | Glass:Clear (T3-1/2),# of Filaments:1,Watts:55,Base:Pigtail (PK22S) | View on Amazon |
| WAGNER | 1213H3 | 🇲🇽 MX | Glass:Clear (T3-1/2),# of Filaments:1,Watts:55,Base:Pigtail (PK22S) | View on Amazon |
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | H324V | 🇲🇽 MX | Front | View on Amazon |
| SYLVANIA | H3SZ | 🇲🇽 MX | Silver Star zXeBase Type: PK22 | View on Amazon |
This table covers the bulbs in the fog and driving lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
16 Fog / Driving Lamp Bulb parts are listed for the 2003 Alfa Romeo 166, from WAGNER, PHILIPS and SYLVANIA. WAGNER H3BLX carries the "Popular" badge.
The Extra Bright (improved visibility, but shorter life) section: 6 options from PHILIPS, WAGNER and SYLVANIA. WAGNER H3BLX is listed in this group.
LED (instant-on, long life, energy-saving): 2 parts, from PHILIPS and WAGNER. A representative part number is PHILIPS H3USLED.
The Standard Replacement section: 6 options from WAGNER, PHILIPS and SYLVANIA. PHILIPS H3 is listed in this group.
2 ungrouped parts are not assigned to a grade, with the same engine-level match.
Glove Box Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825LL | 🇲🇽 MX | Long LifeBase Type: W2.1x9.5d | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825ST | 🇲🇽 MX | BlueSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825SL | 🇲🇽 MX | LEDCool White | View on Amazon |
| SYLVANIA | 2825BLED | 🇲🇽 MX | ZEVO | View on Amazon |
| SYLVANIA | 2825BSL | 🇲🇽 MX | LED | View on Amazon |
| SYLVANIA | 2825LED | 🇲🇽 MX | ZEVOCool White | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825 | 🇲🇽 MX | Base Type: W2.1x9.5dWattage: 5.00 W | View on Amazon |
This table covers the bulbs in the glove-box lamp. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
SYLVANIA supplies the 7 Glove Box Light Bulb parts for the 2003 Alfa Romeo 166. SYLVANIA 2825LL carries the "Popular" badge.
The Extended Life section: 1 option from SYLVANIA. SYLVANIA 2825LL is listed in this group.
The Extra Bright (improved visibility, but shorter life) section: 1 option from SYLVANIA. SYLVANIA 2825ST is listed in this group.
LED (instant-on, long life, energy-saving): 4 parts, from SYLVANIA. A representative part number is SYLVANIA 2825SL.
The Standard Replacement section: 1 option from SYLVANIA. SYLVANIA 2825 is listed in this group.
Part numbers include SYLVANIA 2825LL, SYLVANIA 2825ST and SYLVANIA 2825SL, among others listed above.
Headlamp Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | H7LL | 🇲🇽 MX | Long Life | View on Amazon |
| WAGNER | 1255H7LL | 🇲🇽 MX | Long Life | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WAGNER Popular | 9005BLX | 🇲🇽 MX | Long Life80% More Light | View on Amazon |
| WAGNER Popular | H7BLX | 🇲🇽 MX | BritelitePX26D Base | View on Amazon |
| SYLVANIA | H7XV | 🇲🇽 MX | Xtra VisionColor Temperature: 3200 KV | View on Amazon |
| SYLVANIA | H7ST | 🇲🇽 MX | Color Temperature: 4000 KVSilver Star | View on Amazon |
| SYLVANIA | H7SU | 🇲🇽 MX | Silver Star UltraColor Temperature: 4100 KV | View on Amazon |
| SYLVANIA | H7SZG | 🇲🇽 MX | Silver Star zXe GOLDColor Temperature: 4200 KV | View on Amazon |
| WAGNER | H7TVX | 🇲🇽 MX | Truview PlusPX26D Base | View on Amazon |
| WAGNER | 9005TVX | 🇲🇽 MX | HID Look | View on Amazon |
HID (intense white light)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | D1S | 🇲🇽 MX | High Beam and Low Beamwith HID headlamps | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WAGNER Popular | 9005 | 🇲🇽 MX | Voltage: 12.800 Volts (Direct Current) | View on Amazon |
| WAGNER Popular | 1255H7 | 🇲🇽 MX | Low BeamHalogen Capsule | View on Amazon |
| SYLVANIA | H7 | 🇲🇽 MX | Base Type: PX26DWattage: 55.00 W | View on Amazon |
| WAGNER | 2475H7 | 🇲🇽 MX | Low Beam24 Volt | View on Amazon |
| WAGNER | 9005L | 🇲🇽 MX | Long Life | View on Amazon |
This table covers the bulbs that light the headlamps. Typical signs include a dark lamp, a flicker over bumps, or a bulb that keeps failing on one side. Avoid touching a halogen capsule. Repeated failure in one socket is usually the socket or ground, not the bulb.
16 Headlamp Bulb parts are listed for the 2003 Alfa Romeo 166, from WAGNER, SYLVANIA and PHILIPS. WAGNER 9005BLX carries the "Popular" badge.
The Extended Life section: 2 options from SYLVANIA and WAGNER. SYLVANIA H7LL is listed in this group.
The Extra Bright (improved visibility, but shorter life) section: 8 options from WAGNER and SYLVANIA. WAGNER 9005BLX is listed in this group.
The HID (intense white light) section lists 1 option from PHILIPS — grouped under the catalog's "HID (intense white light)" designation — the notes column spells out what sets them apart. PHILIPS D1S is listed in this group.
The Standard Replacement section: 5 options from WAGNER and SYLVANIA. WAGNER 9005 is listed in this group.
Headlamp Socket
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | HP4355 | 🇲🇽 MX | Handy PackBlack | View on Amazon |
| STANDARD MOTOR PRODUCTS | S900 | 🇲🇽 MX | Connector Shape: Rectangleblack | View on Amazon |
This table covers the sockets that hold a headlamp bulb in the housing. Typical signs include a flicker over bumps, melted plastic, or a bulb that will not stay seated. Dielectric grease on the contacts slows corrosion. Do not force a bulb into a heat-damaged socket.
STANDARD MOTOR PRODUCTS supplies both parts for the 2003 Alfa Romeo 166.
This group includes STANDARD MOTOR PRODUCTS HP4355 and STANDARD MOTOR PRODUCTS S900.
LED Bulb Adapter
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WAGNER | CB900590069012 | 🇲🇽 MX | LEDFor 9005 / 9006 / 9012 Bulb | View on Amazon |
| WAGNER | CBH1H3 | 🇲🇽 MX | For H1 / H3 Bulb | View on Amazon |
This table covers the LED Bulb adapters.
WAGNER supplies both parts for the 2003 Alfa Romeo 166.
This group includes WAGNER CB900590069012 and WAGNER CBH1H3.
License Plate Lamp Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825LL | 🇲🇽 MX | Long LifeBase Type: W2.1x9.5d | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825ST | 🇲🇽 MX | BlueSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825SL | 🇲🇽 MX | LEDCool White | View on Amazon |
| SYLVANIA | 2825BSL | 🇲🇽 MX | LED | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825 | 🇲🇽 MX | Base Type: W2.1x9.5dWattage: 5.00 W | View on Amazon |
This table covers the bulbs that light the license plate. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
5 License Plate Lamp Bulb parts for the 2003 Alfa Romeo 166 come from SYLVANIA. The "Popular" part is SYLVANIA 2825LL.
Extended Life: 1 part, from SYLVANIA. A representative part number is SYLVANIA 2825LL.
Extra Bright (improved visibility, but shorter life): 1 part, from SYLVANIA. A representative part number is SYLVANIA 2825ST.
The LED (instant-on, long life, energy-saving) section: 2 options from SYLVANIA. SYLVANIA 2825SL is listed in this group.
Standard Replacement: 1 part, from SYLVANIA. A representative part number is SYLVANIA 2825.
Listed part numbers: SYLVANIA 2825LL, SYLVANIA 2825ST and SYLVANIA 2825SL, plus the other parts above.
Parking Lamp Bulb
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | H6W | 🇲🇽 MX | View on Amazon | |
| WAGNER | 68161 | 🇲🇽 MX | View on Amazon |
This table covers the bulbs in the parking lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
2 Parking Lamp Bulb parts are listed for the 2003 Alfa Romeo 166, from PHILIPS and WAGNER.
Part numbers include PHILIPS H6W and WAGNER 68161.
Side Marker Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 2825LL | 🇲🇽 MX | Long LifeBase Type: W2.1x9.5d | View on Amazon |
| SYLVANIA Popular | 7443LL | 🇲🇽 MX | Base Type: W3X16QLong Life | View on Amazon |
| PHILIPS | 12821LL | 🇲🇽 MX | Longer Life | View on Amazon |
| SYLVANIA | 5007LL | 🇲🇽 MX | Long LifeBase Type: BA15S | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 7443ST | 🇲🇽 MX | Cool WhiteSilver Star | View on Amazon |
| SYLVANIA | 2825ST | 🇲🇽 MX | BlueSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 2825SL | 🇲🇽 MX | LEDCool White | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7443 | 🇲🇽 MX | Base Type: W3X16QWattage: 5.30 W | View on Amazon |
| PHILIPS | 12821 | 🇲🇽 MX | RearOn Trunk | View on Amazon |
| SYLVANIA | 2825 | 🇲🇽 MX | Base Type: W2.1x9.5dWattage: 5.00 W | View on Amazon |
| SYLVANIA | 5007 | 🇲🇽 MX | RearOn Trunk | View on Amazon |
This table covers the bulbs in the side-marker lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
11 Side Marker Light Bulb parts for the 2003 Alfa Romeo 166 come from 2 brands — SYLVANIA and PHILIPS. The "Popular" part is SYLVANIA 2825LL.
Extended Life: 4 parts, from SYLVANIA and PHILIPS. A representative part number is SYLVANIA 2825LL.
Extra Bright (improved visibility, but shorter life): 2 parts, from SYLVANIA. A representative part number is SYLVANIA 7443ST.
The LED (instant-on, long life, energy-saving) section: 1 option from SYLVANIA. SYLVANIA 2825SL is listed in this group.
Standard Replacement: 4 parts, from SYLVANIA and PHILIPS. A representative part number is SYLVANIA 7443.
Tail Lamp Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7443LL | 🇲🇽 MX | Base Type: W3X16QLong Life | View on Amazon |
| WAGNER | 7528LL | 🇲🇽 MX | Long LifeGlass:Clear (S8), Number of Filaments:2, Watts:21/5, Base:Bayonet (BAY15D) | View on Amazon |
| WAGNER | 17916LL | 🇲🇽 MX | Long LifeBAY15D Base | View on Amazon |
Extra Bright (improved visibility, but shorter life)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 7443ST | 🇲🇽 MX | Cool WhiteSilver Star | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | 1156RLED | 🇲🇽 MX | VisionLED | View on Amazon |
| PHILIPS | 7443LED | 🇲🇽 MX | VisionLED | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 7443 | 🇲🇽 MX | Base Type: W3X16QWattage: 5.30 W | View on Amazon |
| WAGNER | 17916 | 🇲🇽 MX | BAY15D Base21.000 Watt | View on Amazon |
This table covers the bulbs in the tail lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
8 Tail Lamp Bulb parts are listed for the 2003 Alfa Romeo 166, from SYLVANIA, WAGNER and PHILIPS. SYLVANIA 7443LL carries the "Popular" badge.
The Extended Life section: 3 options from WAGNER and SYLVANIA. SYLVANIA 7443LL is listed in this group.
The Extra Bright (improved visibility, but shorter life) section: 1 option from SYLVANIA. SYLVANIA 7443ST is listed in this group.
LED (instant-on, long life, energy-saving): 2 parts, from PHILIPS. A representative part number is PHILIPS 1156RLED.
The Standard Replacement section: 2 options from SYLVANIA and WAGNER. SYLVANIA 7443 is listed in this group.
Listed part numbers: SYLVANIA 7443LL, WAGNER 7528LL and WAGNER 17916LL, plus the other parts above.
Trunk / Cargo Area Light Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 6418LL | 🇲🇽 MX | Long LifeBase Type: Festoon | View on Amazon |
LED (instant-on, long life, energy-saving)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA Popular | 6418SL | 🇲🇽 MX | LEDCool White | View on Amazon |
| SYLVANIA | 6418LED | 🇲🇽 MX | ZEVOCool White | View on Amazon |
| SYLVANIA | 6418BSL | 🇲🇽 MX | LED | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SYLVANIA | 6418 | 🇲🇽 MX | Base Type: SVWattage: 5.00 W | View on Amazon |
This table covers the bulbs in the trunk or cargo-area lamp. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
SYLVANIA supplies the 5 Trunk / Cargo Area Light Bulb parts for the 2003 Alfa Romeo 166. SYLVANIA 6418SL carries the "Popular" badge.
The Extended Life section: 1 option from SYLVANIA. SYLVANIA 6418LL is listed in this group.
LED (instant-on, long life, energy-saving): 3 parts, from SYLVANIA. A representative part number is SYLVANIA 6418SL.
The Standard Replacement section: 1 option from SYLVANIA. SYLVANIA 6418 is listed in this group.
Part numbers include SYLVANIA 6418SL, SYLVANIA 6418LL and SYLVANIA 6418LED, among others listed above.
Turn Signal Lamp Bulb
Extended Life
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| PHILIPS | PY21WLL | 🇲🇽 MX | Longer LifeNatural Amber | View on Amazon |
| WAGNER | 17638NALL | 🇲🇽 MX | Long LifeNatural Amber | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WAGNER | 17638NA | 🇲🇽 MX | Natural AmberBAU15S Base | View on Amazon |
This table covers the bulbs in the turn-signal lamps. Typical signs include a dark lamp, flicker, or a bulb that keeps failing in one socket. If the same position keeps failing, replace the socket or repair the ground rather than chasing bulbs.
3 Turn Signal Lamp Bulb parts for the 2003 Alfa Romeo 166 come from 2 brands — WAGNER and PHILIPS.
Extended Life: 2 parts, from PHILIPS and WAGNER. A representative part number is PHILIPS PY21WLL.
Standard Replacement: 1 part, from WAGNER. A representative part number is WAGNER 17638NA.
Part numbers include PHILIPS PY21WLL, WAGNER 17638NALL and WAGNER 17638NA.
Buying Electrical Bulb & Socket Parts for a 2003 Alfa Romeo 166
On this vehicle, the bulb and socket system covers every bulb and socket on the vehicle, from headlamps to instrument-cluster illumination.
- Confirm you have the 3.0L V6 engine — every part on this page is matched to it.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, replace bulbs in pairs so both sides age together, and put a smear of dielectric grease on the new socket contacts.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: Fog / Driving Lamp Bulb and Headlamp Bulb .
Frequently Asked Questions
How many electrical bulb & socket parts fit the 2003 Alfa Romeo 166?
Our catalog currently lists 111 electrical bulb & socket parts for the 2003 Alfa Romeo 166 across 16 subcategories and 4 brands, covering the 3.0L V6 engine. Each part is matched to the engine(s) it fits.
What are the signs of electrical bulb & socket problems on a 2003 Alfa Romeo 166?
Common symptoms include a lamp that flickers over bumps, melted or discolored socket plastic, or bulbs that keep failing early on one side. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.
What should I replace at the same time?
Where labor overlaps, replace bulbs in pairs so both sides age together, and put a smear of dielectric grease on the new socket contacts.
What do the market flags (US, CA, MX) on each part mean?
They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 2003 Alfa Romeo 166 was originally sold in the US, the safest choice is a part marked for the US market.
How do I make sure a part fits my 2003 Alfa Romeo 166?
Every part on this page is matched to the 3.0L V6 engine. Then repeated bulb failure in one position usually means a socket or ground problem, not bad bulbs — replace the socket rather than chase it. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 2003 Alfa Romeo 166
Electrical Bulb & Socket Parts for Other Alfa Romeo 166 Years
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Manufacturer names, model designations and part numbers are used for identification and fitment reference only. AutoFactsDB is an independent catalog and is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer displayed on this page.