: 2002 HID Conversion--Will I Burn Up Factory Wiring without Using a Relay Harness??

08-22-09, 01:07 AM
Hi...I am considering a plug-n-play Philips (hopefully genuine) HID conversion kit with ballasts and bulbs...but only some offer a relay to be connected to the battery. Is it necessary to run this extra relay, or can the stock headlight harness handle the extra draw at the startup of the HID bulbs?

Thanks for the all your recent help!

08-22-09, 02:22 AM
some people a while back complained they had to flash the brights to get enough power to spark the ballasts on. They put relays in and solved the problem. I had a 00 s10 and the same thing happened.

For an extra $10-15 for 2 relays and some wire.... and 20 mins of time..... why not?

08-22-09, 04:30 AM
That is odd - usually the factory wiring is already relay switched ie. headlight relay??

08-22-09, 10:34 AM

08-22-09, 11:22 AM
So how would I hook up a relay...I understand that the HID bulb plugs into the ballast and the ballast plugs into the factory harness. Where would I install the relay to run to the battery terminal?

08-22-09, 08:19 PM
That is odd - usually the factory wiring is already relay switched ie. headlight relay??

The HID's require a bit more power to ignite the ballast. Only for a second or two. It is best to just hardwire a relay in its place so it gets direct 12v + ....

Follow this guide, its pretty simple...


08-22-09, 08:59 PM
What does "to earth" mean? Also, if I understand correctly...HID bulb to ballast, ballast to stock wiring (or in the case of a relay, ballast to relay harness, relay harness to stock wiring on one light, relay harness to battery terminal). Am I missing anything?

08-22-09, 09:37 PM
earth is ground, AKA "negative" AKA " - " ..... pretty much got it, just follow the diagram and you should be good...

08-26-09, 08:27 PM
I also agree on using relays. When I got my 02, driver's side headight was not functionning. Upon checkup, wiring inside was melted due to a former HID install (I found the ballast in the bumper!). Strangely nuthin on the passenger side.. Diagram posted above should read 87 connection (standard relay wiring) instead of 37.