To wire up an HID kit on the low beams of your Mazda 3 2005, you will need 3-4 things:
1- HID kit (bulbs and ballasts)
2- HID relay (connects your hid kit to your battery)
3- 4700uF capacitor (solves DRL flickering issue)
4- H7 hid bulb adaptor (you can also use the rubber piece that holds the bulb wires as a spacer)
Tips on How to wire up:
1. HID bulb's amp wires connects with the ballast's amp wires. (There's only one way to connect them.)
2. The positive and the negative spade connectors from the hid relay connect with your vehicle's low beam connector, closest to your battery: the driver side. The passenger side low beam connector is not used and should be insulated. You can use electric tape.)
3. Each ballast is connected to one of the relay's clip connector, and it's grounded on each side to your vehicle's body. (One connector for each ballast, one for each side. You can use the screw for the body as a ground.)
4. The red wire(with the inline fuse) in the relay connects to your battery's positive terminal.
5. The capacitor sits on the relay switch. (Google for how to wire the capacitor onto the hid relay switch.) dynoxg image
6. The halogen bulb sits on an adapter. You can safely remove them from each other, and use an H7 hid adapter instead.
For more help: Moonlight Driving