ssrider

I just purchased an HID kit for my 99 Tahoe, i hooked everything up correct, checked about 5 times, and they do not power on, normal headlights do but not the hid when i plug them in, the ballast for the kit i hooked up to my cobalt and they work, as well as the bulb, but when i plug them into the harness of the tahoe, nothing.... any ideas?

Fast55

I'd guess that if you put a meter to the wiring in the Cobalt VS the Tahoe, you're getting a higher voltage out of the Cobalt (much newer car) and you're not getting enough to get the ballast to fire. In older vehicles especially, you might need a direct connection to battery power through a relay. Stick the ballast directly to the battery and see if it lights off then.

ssrider

Tried running directly to battery, still no fire... im normally pretty good with things like this but i hate to say I am dumbfounded right now... lol. Maybe it will only run from battery or alternator while vehicle is running? more amps?

Fast55

That only makes sense if you have a bad battery but I assume the truck starts and runs normally? Where are you grounding the ballast, at the headlight connector itself or also direct to the battery? The HID ballast actually draws less power than the stock bulb (35W VS 55W). Is it both ballasts? It could be a bad ballast that is intermittant regardless of the applied voltage.

ssrider

yeah it is both ballasts, I had the wiring harness for plug and play first time, then when i grounded it i just ran two wires from the battery post, i will try today to see what i can find out, not making any sense to me either. thank you for your posts though

KeithKman

GM cars are reverse polarity. One of the only car manufactures that does this. Plug your HID Ballasts into the head light connector backwards. They should work.

I just installed HID's in my 2001 Tahoe.

ssrider

tried that as well, i am going to go to an auto store tomorrow and get a few relays and just run them throught relays to try and get a higher voltage to them that will hopefully ignite the ballast.

Kmann1994

Did you flip both the HID Harness's Plug AND the original headlight plug?

in2pro

Kmann1994 Welcome to the forum...this is a fairly old post..I'm hoping by now its been resolved after 2 years

Kmann1994

Thank you! I realize how old it is...but I still need an answer to my question up there ^^ I have a 2001 Suburban.