Cadillac CTS 2015 Bulb Size
Bulb size chart
This 2015 Cadillac CTS bulb size guide helps you verify the correct bulbs by lighting position before you buy replacements. Whether you are changing a headlight, tail light, brake light, or interior lamp, this page organizes the common bulb fitments for the 2015 CTS so you can match the right part to the right location.
The 2015 Cadillac CTS was offered in different body styles and lighting setups, so bulb type can vary by trim, package, and market. Use the bulb chart for the exact position you are servicing, and compare it with the bulb already installed in your car to make sure you get the correct fit and function.
Fitment can differ between sedan and coupe models, and between halogen and HID or LED-equipped vehicles. For example, some headlight and daytime running light applications use different bulb types depending on the package, and aftermarket LED conversions may not match the original beam pattern or connector style. Before ordering, check the bulb currently installed, confirm the socket and base style, and verify whether your CTS has factory LED, HID, or halogen lighting so you avoid buying the wrong replacement.
FAQ
What is the best way to confirm the correct bulb for my 2015 Cadillac CTS?
Start by matching the lighting position on the vehicle, such as low beam, high beam, tail light, or license plate light. Then compare the bulb type listed for that position with the bulb you remove from the car. This is the safest way to confirm fitment on the 2015 Cadillac CTS because trim and body style can change the required bulb.
Do sedan and coupe versions of the 2015 Cadillac CTS use the same bulbs?
Not always. The sedan and coupe can use different headlight, parking light, side marker, and turn signal bulb types. Always check the body style first, then use the bulb position listed for that specific version of the 2015 CTS.
What bulb does the 2015 Cadillac CTS sedan use for low and high beams?
The sedan listing shows D3S for the headlight bulb high beam and low beam application. That means the sedan uses a HID-style setup for those headlight positions on the listed configuration.
What are the low beam and high beam bulbs for the CTS sedan with halogen headlights?
For the sedan, the low beam bulb is listed as H11 and the high beam bulb is listed as H9 on the applicable halogen setup. Always confirm your headlight type before ordering, since the sedan can have different lighting packages.
What bulb is used for the front fog lights on the 2015 Cadillac CTS?
The front fog light bulb is listed as H11 LED or H16 LED. Because fog light fitment can vary with trim and lighting package, it is a good idea to verify the bulb already installed before purchasing a replacement.
What bulb size is used for the reverse lights on the 2015 Cadillac CTS?
The back up reverse light bulb is listed as 921. This is a common bulb type, but you should still confirm the socket and bulb style on your specific CTS before buying.
Which bulbs are used for the license plate and dome lights?
Both the license plate light bulb and dome light bulb are listed as 2825 or 98. If you are replacing interior or plate lighting, check whether your vehicle uses the same bulb in both places or a different installed variant.
What bulb does the coupe use for the low and high beam headlights with HID headlights?
For the coupe with HID headlights, the headlight bulb high beam and low beam application is listed as D1S. This is different from the sedan listings, so body style and headlight package matter a lot on the 2015 CTS.
What are the coupe daytime running light and front turn signal bulb types?
For the coupe with HID headlights, the daytime running light bulb is listed as 5201 and the front turn signal bulb is listed as 12272NA. These are specific to the coupe lighting configuration shown on the page.
Are the tail lights, brake lights, and center high mount stop light LED on the 2015 Cadillac CTS?
Yes, the listed tail light bulb, brake light bulb, and center high mount stop light bulb are LED. That means many rear lighting functions on this model are integrated LED setups rather than simple replaceable halogen bulbs.
What interior bulbs are listed for the 2015 Cadillac CTS?
Interior bulb listings include 2825 or 98 for the dome light, 906 for the glove box light and interior door light, 2886X for the stepwell light, 6612F for the vanity mirror light, 211-2 for the trunk or cargo area light, and PC175 for the map light. These positions can vary by trim and equipment level, so check your vehicle before ordering.
Can I upgrade my 2015 Cadillac CTS bulbs to LED aftermarket replacements?
Yes, many owners choose aftermarket LED replacements for certain positions, but fitment and performance can vary. Make sure the bulb base matches, the bulb fits the housing, and the light pattern remains safe and legal for road use. For headlights and fog lights especially, check compatibility carefully before converting.
Why does my 2015 Cadillac CTS bulb type not match another CTS I looked at?
The 2015 Cadillac CTS could have different bulbs depending on sedan or coupe body style, factory lighting package, and market. That is why one CTS may use a different headlight or parking light bulb than another. Always use the exact position on your own vehicle as the final reference.