What Size Bulbs Does a 1999 Infiniti Q45 Use?
Correct headlight, fog light, and tail light bulb sizes. Sourced from OEM catalog data.
Installation Difficulty
Easy (Plug and Play)
Est. Replacement Cost
$50 - $150 (HID System)
What Lighting System Does the 1999 Infiniti Q45 Have?
The 1999 Infiniti Q45 features an extensive lighting system with 11 bulb positions. It uses factory HID/Xenon technology with D2R projector headlights. The Q45 has been available from 1998 to 2001, and the 1999 model falls in the mid-generation years.
Can You Put LED Bulbs in a 1999 Infiniti Q45?
The 1999 Infiniti Q45 comes equipped with factory D2R HID/Xenon headlights. These already produce significantly more light than halogen bulbs, so upgrading is generally unnecessary. When your HID bulbs burn out, replace them with OEM-spec D2R HID bulbs to maintain the correct color temperature and beam pattern. Avoid cheap aftermarket HID bulbs as they can produce incorrect beam patterns and blind oncoming drivers. Your fog lights use a H3 LED halogen bulb, which can be upgraded to LED for a whiter color match with your HID headlights.
How to Replace Bulbs on a 1999 Infiniti Q45
To remove the headlight bulb, disconnect the wiring harness, then twist the bulb counter-clockwise and pull it straight out of the housing. Older model years like the 1999 Q45 typically offer easy access to the headlight bulbs from behind the headlight assembly under the hood. Most owners can complete the swap in under 10 minutes per side. HID headlights operate at high voltage. Always disconnect the battery before working on the headlight assembly. Never touch the HID ballast while the headlights are on, and handle the D2R capsule with gloves to avoid oil contamination. The fog lights are accessed from underneath the front bumper. You may need to remove a few plastic clips or screws from the fender liner to reach the H3 LED fog light socket.
Full Upgrade Bundle
Upgrade All 11 Positions at Once
1999 Infiniti Q45 Complete Bulb Size Chart
| Position | Bulb Size | Shop |
|---|---|---|
Low Beam | HID-D2R LED | Buy HID-D2R LED |
High Beam | HID-D2R LED | Buy HID-D2R LED |
Fog Light | H3 LED | Buy H3 LED |
Brake Light | 921 LED | Buy 921 LED |
Side Marker | 1157NA LED | Buy 1157NA LED |
Turn Signal Front | 1157NA LED | Buy 1157NA LED |
Turn Signal Rear | 7440 LED | Buy 7440 LED |
License Plate | 168 | Buy 168 |
Parking Light | 1157NA | Buy 1157NA |
Reverse Light | 921 | Buy 921 |
Trunk Light | 158 | Buy 158 |
Want to upgrade everything at once?
Shop Complete LED Kit for 1999 Infiniti Q45How Long Do 1999 Infiniti Q45 Headlight Bulbs Last?
HID/Xenon headlights on the 1999 Infiniti Q45 typically last 2,000 to 3,000 hours, or about 4 to 6 years of regular driving. As HID bulbs age, they shift color toward pink or purple, which is a clear sign that replacement is needed. Flickering on startup also indicates a worn bulb or failing ballast. At 27 years old, the original bulbs on your Q45 are likely overdue for replacement. Even if they still illuminate, reduced brightness significantly impacts nighttime safety. When one headlight burns out, replace both sides at the same time. Bulbs from the same batch age at similar rates, and mismatched brightness is distracting to oncoming drivers.
What Bulbs Are Compatible with the 1999 Infiniti Q45?
Using the wrong bulb size can cause improper beam patterns that reduce your visibility and blind other drivers. It can also cause overheating inside the headlight housing, potentially warping the plastic lens or reflector. Always verify the bulb number before purchasing.
1999 Infiniti Q45 Headlight FAQ
Did Infiniti Q45 Bulb Sizes Change Over the Years?
Over its production run from 1998 to 2001, the Infiniti Q45 has seen bulb size changes in the Low Beam, High Beam and Reverse Light positions. The 1999 model uses the newer bulb specification introduced around 1999. Always verify the exact bulb size for your specific 1999 model year using the chart above, as using the wrong size can result in poor fitment or reduced light output.
Other Q45 Years
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