Hello all,

I have a 2003 MCS with xenon headlights. During the late fall/early winter, the passenger side low beam started operating intermittently. One day it would work, the next it wouldn't. Sometimes it would not work when I first started the car, but after I had warmed the car up doing errands it would work when I got back in the car. Sometimes it would flash momentarily as I flipped the switch, which led me to try switching the switch multiple times to get the lamp to light.

This worked for a while. Until it didn't. After limping along like this for a while it got to the point that no matter what, it just wouldn't work whether warmed up, switched on 20 times, or cursed at.

It was winter and I don't have a garage, so I put off doing anything about it. I read a little bit about the typical problem here on this forum, namely the igniter. I also found some reports elsewhere that the control module sometimes goes bad. I waited for warmer weather, drove that way for a few months, and tried not to drive at night. I hoped it would start working with warmer weather. It didn't.

Roughly a week ago, I got to work. After disconnecting the battery, I pulled the cover, pulled the socket from the lamp, and pulled the lamp. I found that I had a cracked lamp. Aha, so it was just a bulb after all! Or so I thought.

After I waited for my replacement bulbs to get here, I replaced the bulbs yesterday. The low beam on the passenger side still did not work. So it was a compound problem. I then swapped the control module with the one from the drivers side, but the problem did not move. So it was likely that wonderful igniter problem. Because 2003 is pre-facelift, the igniter is built into the headlight assembly. Wonderful. I pulled the headlight assembly and spent the evening trying to find a reasonable price for a replacement.

I awoke from sleep early this morning and it occurred to me that moisture might be the culprit. I took the whole assembly and cleaned it up. What follows worked for me, but I don't recommend it for you unless you have the proper equipment and/or facilities.

1. I opened the rubber covers from the units to expose the internals of the assembly to atmosphere.
2. I put the cleaned unit in an industrial oven with proper ventilation and heated the oven to 250 deg. Fahrenheit. I chose this temperature to be high enough to vaporize water but low enough not to do damage to any of the headlight assembly components and to minimize outgassing.
3. I baked the headlight assembly for 3 hours, and let it cool.
4. I reinstalled the assembly on the passenger side.

It works!

It will be interesting to see how long it works for. If it fails, I will make sure to post here that it has done so.

 

Good luck!

My 02 xenon went in and out for a while too. Now it almost always works, but is now much brighter than the other side. Im sure it's just a matter of time before it explodes lol.

I also did some reading about the ignitor and module. It seems like just getting a new headlight assembly is the way to go. From what I've read the newer headlights should be a direct fit. Hopefully that info is correct.

The ignitor is expensive and I couldn't find any info pointing to the correct one for our early xenon model. I found some, but it is going to be a guess to get the right one.

 

Hello there,

Just checking to see if you still have that R53 and how the passenger side headlight is doing. I'm starting to have the same issue with my 2003 R53.

Thanks!

 

Did not get a notification of your post. Still have the R53. I had problems.. and replaced the xenon headlights with the base units.

 

I'm curious if you also saw wire insulation degradation with your preface-lift R53 Xenon's? I have a 2006, and the wires in the headlights had lost most of their insulation. It just crumbled off the wire. When one light went out, and I was troubleshooting, I noticed the bare wires. The igniter was also bad; not sure if the bare wires shorted and blew out the igniter.

 

I don’t recall any degradation of the wire insulation. I absolutely would have noticed that.

I don’t know why, but I still hold out hope that one day, I’ll return to Xenon headlights. When installing new control arms today, I took great pains to make sure the leveling sensor was properly located on the left control arm, in case I ever do manage to refit Xenons.

 

I never saw any wire degradation with my original pre-facelift R53 Xenon headlights. However, when upgrading to the facelift projectors, I discovered that the sheeting around the wires were severely deteriorated and completely crumbled. Most common with the facelift projectors.
I completely rewired both headlights - What a PIA. But well worth the upgrade to projectors. It's been about 4years now with no problems.

 

That is interesting. I asked because I was wondering if this problem was new to the facelift generation.

Here2Go- you said you rewired the headlights... did you take them apart to access all the wiring? I put heat-shrink tubing on the wires I could and then applied liquid electrical tape to everything else I could reach. I would love to do it right and rewire it all, but I didn't see a way to access all the wiring. Maybe taking the lenses off with heat is the way to do this?

 

My apologies if I mispoke - From what you wrote in your procedure; I pretty much did the same.
I remember removing the square cover and bulb housing caps to gain the most access to the furthest reaches where the wires loom. Using a pair of long cuticle sissors and various long tweezers and hemostas, I was able to get in there quite far and removing/replacing a fair amount/all of degraded wire. I also remember modifying my soldering iron improvised with a long piece of brass rod. I wrote a post with pictures about what I did back then but I can't seem to find it in my profile. If I recall, there is not much that can be removed from the back of the housing to gain better access. I did have a spare headlight where I was able to remove the lense but ran into trouble trying to figure out how the inner chrome reflector was attached. I think there were some torx screws that were buried behind the chrome which were almost impossible to get to with the tools on hand. However, I can't recall seeing better access to the wires behind that inner reflector. Although, I could be wrong.
But yes, like you; I ran heat shrink around the repair using my butane pen and or a hairdryer.
Not much evidence to show the results - but I would venture a guess that our process and repair are about the same.

 

Thanks for clarifying and the additional details, including the inability to access additional wiring if the lens is removed.

To be clear, I didn't replace any wiring; I just covered the bare wires with either heat shrink tubing or liquid electrical tape. Before I put my R52 away for the winter, I noticed that one of the headlights was out again. I have to troubleshoot that in the spring when I get it back out.