wakko

I had a set of aftermarket xenon / HID hardware installed today on my 2001 A4 1.8T and the "headlight defective" warning symbol comes on my display whenever I fire up my new lights.

Anyone else experience this problem? Is it possible to disable the head light warning signal?

TIA

WayneRx

Are you drawing power directly from the battery with wiring harness and relays? My friend who installed the HID for me said this is a safer set up. I wonder if anyone has a solution to this?

QuattroRocket

Thats odd ... my kit plugged directly into the stock plug and wiring and I have had no problems at all.

Ag TT

I think it's the relays that came with the xenon kit. I believe the only way to get rid of the warning is to power the ballasts directly from the stock power leads for your old low beam halogen lights. That way, you bypass the relays that came with the kit and the problem should go away, but you may fry the lighting circuitry.

When you first turn the xenon lights on, the ballasts draw quite a bit of electricity to create a very high voltage to strike the xenon bulbs. There is a reason why the kit came with the relays.... it's to create a separate circuitry so you don't fry your car's circuitry when you turn the lights on. It's annoying, but buys a peace of mind.

wakko

Yes, my HID comes with relay; but unfortunately only on the passenger side. Supposedly, the place that I got it from told me that it will stop the circuit if there is any problem, so no need for the driver side to also hook up with a relay.

Anyways, good that I know I am not the weird one. I've had the problem for almost a month. Slowly but surely this is getting to me =(

James R.

you need to find out what the threshold for the headlight blown dectect circuit is and make sure you draw at least that amount of current.

Basically, my guess is there's a very low value resistor, a current shunt which the cluster monitors. If the headlight switch is in the on position and there's no voltage drop across this small resistance it knows there's no current and it says, "bulb blown" or whatever. So you need to find out what the minimum current you need to draw is and calculte the appropriate resistor value based on that calculation. Once you've done this you can buy a large power resistor and hook it up in parallel with the relay coil which is now switched by the old headlamp control wires and I PROMISE your problem will go away. Problem is...the minimum current could be quite high, if that's the case you might end up with 50W resistors etc...which still beats the heck out of a warning light on your dash all the time.

Regards,

James R.