My left headlight has been flickering slightly for about a month, only when it’s REAL cold out. Today it didn’t turn on once but then turned on again after I toggled them off/on.
Is this a bulb or ballast issue? :gotme:
Sounds like the bulb(s) are getting old.
As an HID bulb ages it slowly burns up the electrodes (Similar to the tungsten tips when TIG welding); as the gap widens it takes more and more voltage to create the initial arc and then maintain the arc. Once this voltage increases above what the ballast/igniter can provide then you get what you’re seeing.
The flickering you’re seeing is the arc moving around on the electrodes looking for the least resistance point as the electrode burns away and changes shape. This gets worse the older the bulb gets.
Nice. That’s a $150 part vs. a $1,400 part 
And if you paid that much for HID’s, major facepalm. Just get aftermarket shit.
Josh I have a few random HID bulbs kicking around that might work in your setup if you wanna try one out. I was just having this issue with a brand new philips bulb.
HID singular; that’s the cost for one factory Range Rover headlight assembly. My passenger side lamp did the same thing a few times and the dealership replaced the whole headlight assembly under warranty. If it was just a bulb, why they gave me a whole new headlamp is beyond me. I kinda figured I was going to need to do the same for my drivers side but if it’s just a bulb that’s easy.
I don’t really want to mess around with random bulbs. I’m afraid the color might look different! I’m sticking with OEM parts.
I have OEM bulbs. Do these share bulb with BMW as mine are for the M5. I have 3 diff sets lol.
It’s a D2S bulb.
Wrd, I will check when I am out there again. I think you should at least put one in even if not oem to see if it clears up the issue for sure before you order the new bulb. I am pretty certain I have that style.
Awesome thanks!
Also I have a good bulb guy lol this is one of the reasons I have a few sets. What is your OEM GE or Philips I assume? LMK I bet I can get you one for ~100 easily.
They’re OSRAM D2S 84V 35W 4,100K
WTFFFF lol I can call tomorrow. Otherwise feel free to stop over and try one of my bulbs to see if it deff fixes it. I will be around all day Sunday in the garage getting some much needed wrench therapy.
i believe that d2s is the same as bmw. however normaly when a bulb goes bad it begins to change color first to a pink color then it just stops working. this sounds like an ignitor/balast issue which is why rover changed the whole assembly for you last time.
My dealership paperwork says “internal short” as the reason for replacement on the other light when it was doing the same thing. No color change has happened.
Do you see a color change in an HID style bulb?
Did you try just swapping bulbs first from left to right? If the problem carries over to the right then you know it’s the bulb, if not, it could be the ballast or even a bad connection.
Flickering at startup could be caused by both the bulb AND ballast. Its actually more likely its the ballast in most cases. Do not buy anything other than the exact OEM part. The bulbs are not very expensive if you don’t get them straight from the dealer.
How old is the bulb and ballast? It would generally be at least 5+ years before you see any issues with a OEM HID system. Swap the bulbs from side to side. Make sure to wiggle the connector on the bulb to ensure a clean connection.
It doesn’t flicker at start up - it flickers when it’s cold out.
It’s 5 years old so I guess it’s close to replacement time anyway. I’ll try swapping bulbs.