Knightmare69

Asking because I've spent the past 2 weeks off and on troubleshooting my fiance's 2010 Avantgarde that we installed HID's in the fogs. I originally got a standard kit with the thick ballast, had it tested at the shop off a battery and works fine, installed it on the benz and flicker flicker random off/on.

Ok, so order a relay harness and reinstall, now it doesn't even work, swap relays just in case, nope, still not working. Bridged the relay's to test if both relays were shot and nope, the HID's work when the relays are bridged so it's not the relays.

Order new ballasts, slim design this time. Reinstall everything again and it's seemingly more stable this time, but still flickers and random off/on. So troubleshoot again, ran ground off the chassis instead of oem harness, no change. Thought maybe it was the power so redid the power wire to ensure better connection, no change.

Everytime, I retest the kits off battery I have no problems. Even thought maybe it was the bulbs so ran the kit off the battery and let it sit for a while and no flicker, no off/on problems.

I noticed though that when idling the kit stabilizes after the initial off/on and flickering but when driving it doesn't flicker, just completely shuts off/on. I've come to the conclusion that there's gotta be an issue with the power source for the fogs where it's not consistently flowing. In the end, I pulled it all out and swapped back in my Piaa ion yellow bulbs.

Sorry for the rant but figured it could serve as a warning to other avantgarde/lux owners that our models may not be suitable for HID fogs. I know alot of sport owners have HID fogs and I'm not sure if those H7 fogs have something different with the wiring but they seem to have no problems.

BTW, everytime I installed the kits I never got a dash warning light and I doubt error cancelers would've helped if the relay kit couldn't and all ballasts were 35W versions.

Petje

May be the positive wire dont give a constant voltage. This can cause the flikkering issue with HID

Petje

So if the HID does normall on a battery , this can be the issue

Knightmare69

Yea, that's the conclusion I came to which is why I think the relay also didn't work out as it wasn't constantly powered. However I don't understand why HID's work on sport model fog lamps. Is it really possible there's a wiring difference?