If you don’t want to read the entire post I’ll summarize: BUY A WIRING HARNESS TO PREVENT DAMAGE TO YOUR EXISTING WIRING HARNESS
Why do I need a relay harness?
Some vehicles might be able to power up HID systems normally without problems at install time. It will probably not last long. The inrush load can be up to max 13 amps per ballast, compared to 7amps inrush when using halogen. The factory design parameters for headlight circuits are 7 amps inrush and 4.5 amps continuous load. So over time, connectors, multifunction switch, headlight switch, wiring and fuse holders will slowly degrade, because of heat buildup. These components are very time consuming to troubleshoot because they are usually well hidden behind dashboards and other wiring looms. Parts can cost several hundred dollars and add 8h labor to that and it becomes obvious that a $25 wiring harness is a cheap insurance.
â€¢ My HID system does not turn on the bulbs, or bulbs flashes/flickers, or needs the engine to run.
â€¢ Start power is up to 13Amps. If power is fed from stock wiring, a voltage drop will happen and 12volt system voltage at ballast goes under 9volts. Install wiring harness as described below.
â€¢ If you have a proper wiring harness installed, look for corrosion in contact elements.
â€¢ If bulb, igniter or ballast is of non OEM quality(typically HID kits), some or all parts will break within 3 years.
â€¢ If you have quality HID parts, you could swap parts from one side of the car to the other. Downside of doing this is that a any defective component can destroy other perfectly working parts.
My HID bulb restarts when I am using my high beams
The actual “dark” time interval between low/high beam shifts might not be visible when you run halogen bulbs. Halogen bulbs react a little slow, so it is hard to notice. We are talking of maybe 1/10 of a second. But any HID system will turn off and restart. What you experience on the road is dangerous pitch dark, 3-5 seconds.
This can be solved a few ways, the first one is the most elegant:
1. Connect triggers wires of the relay(s) that feeds ballasts directly to headlight switch, electrically before multifunction stalk. Having wiring diagram available is recommended. If not, you can simply obtain access to rear of headlight switch, and try out the different terminals using a 12V test lamp.
2. Adding a large capacitor between + and – on the trigger terminals of ballast relay. The size of the capacitor will naturally vary with size of interval. A starting point could be a 4700uF/minimum 20V. Yes, I know, this is not a small component.
3. If you don’t live in area with fog and you have been driving around with fog lights on because your headlights are poor, you might find that you can use the fog lights switch to trigger your HID low beam. After all, you wouldn’t need any “fog” lights now that you have HID.
4. Simply wire up a new switch. The cool thing is that the switch can be physically very small, since it only need to be rated for 0.3 amps.
5. Connect trigger wire via a 4 second delay to ignition circuit. The delay will turn HID system on after you have started engine, regardless of night or day. So this would serve as a DRL function as well.
6. Connect trigger wire to the park lamp circuit. This will eliminate all problems related to high beam usage. Park lights are always on regardless of “flash to pass”, and low beam/high beam mode.