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One headlight is not like the other

I have a 2007 Nissan Murano with roughly 50,000 miles on it. I have those HID bulbs, or whatever you call them, that are real bright (but not blue or purple). As recommended by the dealer, I’ve always had the headlights set on Auto so they turn on and off based on how the sensors sense ambient light. My left light started to flicker and shut off intermittently. If I turn them off then back to Auto, the left light comes back on. I took it into the dealer and they determined that the bulb itself was shorting out. My question(s) would be what would cause that to happen and why would it affect one side but not another? Inquiring minds want to know because the dealer wants to drain my wallet for over $300 to remove and replace it. Many thanks.



Lance, Pasadena, CA

The filament in the bulb is what causes it to glow, it is basically a point a to point b connection. Occasionally a part of the filament can fail, but the remaining part may make contact on an intermittent basis. The bulbs these days are many times replaced in pairs. If you are at all handy you can do it for a fraction of the price.

I’m not familiar with the details behind the Murano HID wiring but odds are there are ballasts involved (one for each side) so they’re operating independently of each other.
Hopefully the diagnosis is correct and the problem is not related to the ballasts, etc. as that could be even more expensive.

At to pricing, HID lamps are expensive to repair on any vehicle and some are far more pricy than 300 dollars.
The later Lincoln Marks used an HID system and I’ve seen USED bulbs sell for 2-300 dollars on eBay. A complete lamp assembly from the dealer was about 2400 dollars.
For that kind of money I’d probably just stick a couple of magnetic flashlights on top of the fenders and call it good.

So back your car slowly out of your dealership while no one is looking and tries to sell you anything else.
Your parts will run between $8 each and $35, you need two Xenon HID bulbs. Yes, the lamp involves an inert gas and does require a ballast. But I’d bet that the lamp is bad. Do replace both.
You can replace the lamps without tools with a dexterous hand and some patience. Or else get it done at a local garage for $100 tops.

HID headlights do not have filaments in the traditional sense. They are more like fluorescent lamps. And way too expensive to replace in pairs.

You should be able to get this replaced for about half that price. Try to get the bulb elsewhere besides the dealer. A non-dealer mechanic will be much cheaper on labor too. The electronic ballast could be failing, and that won’t be nearly as cheap, but the bulb’s a good place to start.

I don’t see a reason to replace HID lamps in pairs. Their life expectancy isn’t as predictable as a halogen lamp, and they do not usually dim or change color with age. If you replace one and it looks significantly different from the remaining lamp, then replace the other.

Thanks everyone for the input. It’s greatly appreciated!