Q about bench testing Xenon HID headlights

[Dave Doolittle]

I picked up a pair of what I believe are bi-xenon headlights recently and am trying to bench test them. They came from a 2003 A4 that's being parted locally. Part numbers are 8E0941030K and 8E0941003AA.

I found this pinout diagram here on Audizine:


The high beams come on in both assemblies by hooking up the wires from the connector terminals 1 & 8 to a battery.

Should testing the low beams, which are powered by the ballasts, be as simple as hooking up terminals 5 & 10 to the same battery?

They're not coming on with that test am I'm curious if I've missed something or if I simply need to dig deeper into the system and figure out if it is bulbs or ballasts. The fact that both are not powering up makes me wonder if I'm missing something. I have swapped bulbs between units with the same results.

My wiring plug is slightly different in that it does have a wire on terminal #3. It's a very small gauge gray wire with a black stripe.

Any input would be appreciated.

Also, if anyone could provide a wiring diagram specific to the 2003 model year it would be greatly appreciated.

Any other questions I should be asking here?

Thanks.

[evo_ski]

You can also simply wire directly to the ballast like so.



What exactly are you trying to bench test? Just to make sure the ballasts and bulbs work? If you post pictures of the lights I can tell you if they are bixenon or not.

[Dave Doolittle]

Thanks. Do you need other views to confirm the bi-xenon function?

I picked these up used & untested, and am trying to determine if I can pass them on, representing that they're fully functional, or if I need to part them out as just housings and other misc parts that might actually work.

Can the xenon bulbs be reliably tested with an ohm meter? It looks like they have 3 terminals. I get infinite resistance across all combinations.

[diagnosticator]

Those headlights are not bi-xenon. They are low beam only HID xenon. Regardless, energizing the low beam power to +Bat and ground to -Bat, should cause the low beams to turn ON. A frequent fault occurs with xenon lights, at the ballast power supply connector. The female terminals can get loose and fail to make contact with the pins. You can gently bend the contact spring in the female terminals to press on the mating pins with the connector engaged in the ballast connector socket. Otherwise, there is a fault in the ballasts or HID lamps. The xenon lamps cannot be tested with an Ohm meter.

[Dave Doolittle]

Thanks. My understanding of the bi-xenon feature is that a shutter moves back and forth when switch from high to low beam that affects the throw of the light, in concert with the standard high beam bulb turning on. Is that right?

I looked at those connectors and they seem tight. fiddled with them and no change. The 'ball' in the center of each xenon bulb is cloudy and there is a slight deposit or haze on the outer tube in the vicinity of the ball, which some internet research says are indicators of bad or worn bulbs.

So, in the absence of a known good xenon bulb to test with, is there any other way to test the ballasts? I'm not about to put a multimeter on the output side when it's energized...

[CyberPMG]

The Bi-Xenon headlight housing doesn't have the chrome on the inside (only chrome is on the shrouds). The back of the Bi-Xenon housing does not indent in around the high beam. The back is straight across. The main beam lens for the Bi-Xenon is also larger (3" compared to 2.5"). On the inside is the actuator to operate the cut off flap to provide full light output from the Xenon bulb (you can press the switch in and out to operate the flap).

As far as bench testing goes, I'll leave that to electrical experts. Simple test would be to find a buddy with a B6 A4/S4 with Xenon lights and try them on their car. Swap bulbs to determine if there's any issue between the bulb or the ballast. The ballast is used for both Xenon and Bi-Xenon headlights. Same goes for the Xenon bulbs.