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17 Years Available

Cadillac Cts Light Bulb Sizes

Complete bulb size reference for the Cadillac Cts from 2003 to 2019. Find headlight, fog light, turn signal, and brake light bulb sizes for every model year.

The Cadillac cts changed low beam specifications across model years — 2003–2015: D1S; 2016–2019: D3S. Make sure to select your exact year below to get the right bulb size.

Year Range

20032019

17 model years

Most Common Low Beam

D1S

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Bulb Sizes Across Years

PositionBulb Type(s)YearsStatus / Shop
Low Beam
D1S(20032015)
D3S(20162019)
17 yearsChanged
High Beam
D1S(20082015)
9005XS(20032007)
D3S(20162019)
17 yearsChanged
Dome Light
2825(20082019)
PC175(20032007)
906(20142014)
17 yearsChanged
License Plate
2825(20032019)
17 yearsConsistent
Map Light
PC175(20032019)
17 yearsConsistent
Reverse Light
921(20142019)
3157K(20032007)
11 yearsChanged
Trunk Light
211-2(20032019)
17 yearsConsistent
Door Light
906(20082019)
12 yearsConsistent
Fog Light
H11(20082015)
9140(20032007)
13 yearsChanged
Turn Signal Front
2825(20032007)
12272(20152015)
6 yearsChanged
Side Marker
194(20082015)
2825(20032007)
13 yearsChanged
Parking Light
2825(20032014)
12 yearsConsistent
Brake Light
PC175(20032007)
5 yearsConsistent
Turn Signal Rear
3157K(20032007)
5 yearsConsistent
Daytime Running
3157(20032006)
3157CK(20052007)
5 yearsChanged
Tail Light
3157(20052007)
3157CK(20032004)
5 yearsChanged

Common Cts Replacement Parts

Select Your Year

Frequently Asked Questions

We have bulb size data for the Cadillac Cts from 2003 to 2019, covering 17 model years. Select your year below for a complete position-by-position bulb chart.

Yes, the Cadillac Cts changed low beam bulb specifications across generations: 2003–2015: D1S; 2016–2019: D3S. Make sure to check your exact year using the list below.

The Cadillac Cts uses a D1S bulb for the low beam (same bulb serves both high and low beam via dual filament), and a H11 for the fog lights. Select your year below for the exact fitment chart.

Yes. The Cadillac Cts uses a D1S low beam, and direct-fit LED conversion kits for that size are widely available. LED upgrades typically produce 2–3× more light output than stock halogen and last 25,000+ hours. Look for a DOT-compliant kit with a proper beam cutoff pattern.

Select your model year from the list below. Each year page shows every bulb position — low beam, high beam, fog light, turn signal, and brake light — with the correct size and a link to buy it on Amazon.