Inside will be the back of the bulb and the wire harness. Rotate the back of the bulb assembly and it should come out. Disconnect the wires and replace it, and put it back the same way you took it out.
Reference this thread
http://www.coremazda.com/forums/mazda6-forum/792-Mazda-6-headlights.HTML
With the help of my brother, I was able to replace the driver side low beam to my 2006 Mazda 6. Above helped a ton but one additional piece of info was missing. There is a spring load on the bulb. After you remove the cap, you need to get a light in there and see the loop which is holding in the bulb. That has to be pressed down and pushed to the side to release the spring and then the bulb can be removed. The bulb I had to turn slightly and then it came right out. Take it out slowly so you can see how the replacement will go back in. The base of the replacment bulb had a flat side so I just kept track of where that was when I removed it. Don't touch the actual bulb...I was told that if you get the oils of your fingers on it, the light will burn out within a week because the oils bake on and cause it to burn out.
Be careful when removing the bulb. It can easily break and leave fragments inside the lens assembly. The wire spring is holding the bottom side of the light and when twisting the light to relieve the pressure on the bottom side, the bulb can break (which mine did).
How do you replace headlight bulb on 2004 Mazda Tribute?
beat the car with a bat
For the 1994 model (B3000), you can't change just the bulb. You have to change the headlight assembly.
newtest3
To replace the headlight on a Mazda Tribute, start by opening the hood and locating the headlight assembly. Remove the retaining clips or screws securing the assembly, then gently pull it out. Disconnect the wiring harness from the back of the headlight bulb, replace the bulb with a new one, and reconnect the wiring. Finally, reinsert the headlight assembly and secure it with the clips or screws.
You will need to take the complete headlight assembly loose or out to get to the bulb to change it.
To replace the headlight bulb on a 1997 Mazda Miata, first, open the hood and locate the headlight assembly. Remove the rubber cover by pulling it off, then twist the bulb socket counterclockwise to release it. Carefully pull out the old bulb and insert the new one, making sure not to touch the glass with your fingers. Finally, reattach the bulb socket by twisting it clockwise, replace the rubber cover, and test the headlight to ensure it works.
what year? and which parking light? side marker or in the headlight? 2005 Mazda 6 side marker light bulb
To replace the headlight bulb on a 2003 Mazda Tribute, first, open the hood and locate the back of the headlight assembly. Disconnect the electrical connector from the bulb by gently pulling it off. Remove the bulb by turning it counterclockwise and replacing it with a new bulb, ensuring not to touch the glass with your fingers. Finally, reconnect the electrical connector and test the new bulb before closing the hood.
To change the left side headlight on a 2005 Mazda 3 hatchback, first, open the hood and locate the headlight assembly. Disconnect the negative battery cable for safety, then remove the plastic cover or the headlight assembly by unscrewing any retaining screws. Carefully disconnect the electrical connector from the old bulb, twist the bulb socket counterclockwise to remove it, and replace it with a new bulb. Reassemble everything by reversing the steps, ensuring all connections are secure.
To replace a headlight bulb on a 2009 Mazda 6, first ensure the vehicle is turned off and the keys are removed. Open the hood and locate the back of the headlight assembly; twist and remove the bulb socket from the assembly. Replace the old bulb with a new one, being careful not to touch the glass part of the bulb, as oils from your hands can cause it to fail. Finally, reinsert the socket back into the assembly and test the new headlight before closing the hood.
To replace the left high beam headlight bulb on a 2003 Mazda 6, first, open the hood and locate the headlight assembly. Disconnect the electrical connector from the back of the bulb and remove the rubber cover. Twist the bulb socket counterclockwise to remove it, then replace the old bulb with a new one, ensuring not to touch the glass with your fingers. Reassemble by reversing the steps and test the new bulb to ensure it works.