Cadillac CTS 2004 Bulb Size
Bulb size chart
This 2004 Cadillac CTS bulb size guide is designed to help you verify the correct bulb by lighting position before you buy replacements. Whether you are changing a headlight, a tail lamp, or an interior bulb, matching the bulb to the exact location is the safest way to avoid fitment mistakes.
The 2004 Cadillac CTS uses different bulb types depending on the lamp position, and some trims or lighting packages can change what is installed. Use this page to compare the bulb chart for low beam, high beam, brake, turn signal, parking, license plate, and interior lights so you can narrow down the correct replacement quickly.
For best fitment, always confirm your CTS trim, body style, and lighting package before ordering, since halogen and HID setups use different low beam bulbs. If you are switching to LED bulbs, check the physical size, polarity, and space inside the housing, because some aftermarket LED conversions may not fit or may trigger warning issues. It is also smart to inspect the bulb already installed in the vehicle and compare the base style before purchase, especially on exterior lights where market differences and previous repairs can affect what is actually in the car.
FAQ
What low beam bulb does a 2004 Cadillac CTS use with halogen headlights?
A 2004 Cadillac CTS with halogen headlights uses a 9006XS low beam bulb.
What low beam bulb does a 2004 Cadillac CTS use with HID headlights?
A 2004 Cadillac CTS with HID headlights uses a D1S low beam bulb.
What high beam bulb fits the 2004 Cadillac CTS?
The high beam bulb listed for the 2004 Cadillac CTS is 9005XS.
What bulb is used for the front outer turn signal light?
The front outer turn signal light bulb is 2825, 98.
What bulb is used for the front inner turn signal light?
The front inner turn signal light bulb is 3157.
What bulb fits the rear turn signal light on a 2004 Cadillac CTS?
The rear turn signal light bulb is 3157.
What bulb is used for the brake light and tail light?
Both the brake light bulb and tail light bulb are listed as 3157R.
What bulb does the daytime running light use?
The daytime running light bulb is 3157.
What bulb fits the back up reverse light?
The back up reverse light bulb is 3157.
What bulb is used for the front side marker light?
The front side marker light bulb is 194NA.
What bulb is used for the rear side marker light?
The rear side marker light bulb is 2825, 98.
What bulb fits the license plate lights?
The license plate light bulb is 2825, 98.
What bulb is used for the trunk or cargo area light?
The trunk or cargo area light bulb is 211-2.
What bulb is used for the dome light and map lights?
The dome light bulb and map light bulb are both PC175.
What bulb fits the center high mount stop light?
The center high mount stop light bulb is PC175.
What bulb is used for courtesy lighting?
The courtesy light bulb is 564.
Do all 2004 Cadillac CTS models use the same bulbs?
Not always. Trim level, body style, market, and lighting package can change the bulb setup, so it is important to verify the exact lamp position on your vehicle.
Can I replace the factory bulbs with LED bulbs?
Yes, many owners upgrade to LED bulbs, but fitment can vary. Check bulb size, housing clearance, and any electrical compatibility concerns before buying LED replacements.
Why should I check the installed bulb before ordering?
Previous repairs, aftermarket parts, or market-specific equipment can mean the bulb in the car does not match the original listing. Checking the installed bulb helps confirm the correct base and size.