misterlawyer

Sometimes when I turn on the headlight switch the passenger side low beam won't turn on. I get a "low beam" malfunction warning in the instrument cluster display several seconds later.

Turning the headlight switch off and on doesn't help.

Sometimes the headlight will start working again if I drive for a few minutes with the headlight switch off and then turn it back on. So then both headlights will work fine for the rest of the trip. It's almost as if the headlight needs to 'warm up' in order to turn on.

The driver's side headlight works perfectly and always has. This problem is only with the passenger's side low beam xenon headlight.

Do I need to replace the bulb? It doesn't seem to be completely "burnt out" because it works intermittently. Is this a problem with the "ignitor" or whatever it's called?

How much will this cost to have a stealership fix or can I do it myself?

Thanks in advance for any help!

diablo2112

Sounds like a ballast problem. You might want to unplug/replug the connection to the ballast a couple of times. Those plugs are in an area that can see water/salt/etc. and the connections can degrade with time. Most likely, it's either that or the ballast itself. These come up on ebay occasionally as part of used R230 headlight assemblies.

glennbaz

For sure the ballast or igniter. Stay away from the dealer as you can like me get both parts together for about $140 on ebay. Problem solved after a very long story.
Glenn

misterlawyer

Thank you, both of you guys. So it sounds like there are three possible culprits: ballast, ignitor, or the connection. All in all, I'd call that good news.

The problem subsided on its own recently, but I'm going to find a few hours of spare time this weekend to get in there and check the connections.

If the problem resurfaces again, I'll be on eBay looking for a new ballast or ignitor. If anybody else has had to deal with this, your input would be appreciated.

Thanks!

kamilclk430

I agree!

glennbaz

You can check for a loose connection but the time it takes to take out the headlight assembly and put it back I would have the "new" parts in hand and swap them out when you don't find a "bad" connection. You can alway flip the parts back on ebay if it turns out to be a connection.
Good luck
Glenn

tkkben

I just replace the ballast in my 2004 sl500. Just to let you all know that the ballast could be accessed from the bottom of the car after removing the plastic shied under the car. Only 3 screws holding it and could be done within half hour. You don't need to remove the whole lamp suggested by others which mean loosing the bumper to access the screw holding the lamp. However ignitor is inside the lamp which you might have to remove the lamp. Bottom line, replacing the ballast for the headlight is VERY easily done from under the car.

moretech

thanks much for this tip! I'll remember this if I ever have a lamp out. We need to get these really good tips into a "group of important solutions" to problems as mentioned by other forum members. That may/would save us time in trying to find the appropriate thread for our personal vehicle problem.
moretech

MacVidMB-V8

Always a good idea to start with just switching the bulbs, left to right. If problem follows the bulb you have an easy answer.