Headlight condensation

[br1anstorm]

I've recently noticed some condensation in the headlights of my 2002 IS300 Sportcross.  A browse through the forum suggests that this is a problem in several models.  There seem to be various possible ways of trying to deal with it - from gentle hairdryer heat, to drilling ventilation holes, to trying to put a dehumidifier sachet into the unit!

I haven't tried to remove the headlamp(s), still less dismantle them.  The first and basic question is - are the headlamp units sealed (or supposed to be watertight)?  If so, then it would seem necessary to check for holes, cracks, or leaks, assuming the bulb/wiring locations and connections are properly sealed, and then repair/seal them up once any moisture has been removed from the inside of the unit.  I've seen a linked YouTube video which shows how to do this on a rear light unit, which was however LEDs.  I assume my IS300 headlamps are HID, which generate a lot more heat.

If however the units are not sealed, then the key would seem to be to ensure appropriate ventilation, and rely on air-circulation and/or heat from the lamp bulb itself, to remove any moisture.  Hence presumably the drilling-extra-holes idea?

So any thoughts or advice on how to get rid of condensation - permanently - would be welcome. Not only is it a matter of effective lighting, I also worry that moisture inside the unit can't be good for the electrics of the lamp itself.....

[br1anstorm]

Five weeks and no replies, which is a bit disappointing.  I have a follow up question.  Can anyone advise on how to remove a headlight,  ideally without removing the front bumper panel.  There is an archived guide in the forum at ....

..... but the links to the various photos/images no longer work.  If anyone can explain how to access those images, I would really appreciate it!

 

[LenT]

1 hour ago, br1anstorm said:

Five weeks and no replies, which is a bit disappointing. 

Yes it is, so perhaps I can pass the time by asking a question of my own.  Is it an equal problem on both lamps?  If you switch to high beam and leave it on for some time, does the condensation fade at all?  I would expect condensation to begin to clear with the heat generated by the bulb, especially if they are HiD.

If this doesn't produce any change at all then, considering the age of the lamps, could it be discolouration of the exterior of the lamp cover?

I also wondered if, as you presumably don't want to buy new lamps, getting replacements from Lexus breakers is a possibility - assuming there are such places.

[br1anstorm]

Thanks Len - good to have the opportunity to discuss this problem.  To answer your questions.... the problem is only with the left (passenger side) unit.  The one on the right is fine and never shows any condensation irrespective of weather conditions.  And I cannot see any chip, crack or hole anywhere on either the front 'glass', or in what I can see of the plastic moulded 'body' of the unit.  So I can't work out how the moisture is getting in.

The condensation doesn't seem to clear (or not very much) with the lights on.  I haven't tried an extended period on high beam though.

Do the HiD bulbs generate a lot of heat?  I've done a bit of internet research.  It seems that halogen bulbs - which have a filament which glows when hot - generate a lot of 'radiant' heat which then heats up the glass in front of it.  HiD bulbs themselves do run hotter (in simple terms the light comes from a "plasma arc" within the bulb - like lightning or an arc welder - which has huge voltage).  But HiD lamps have a lens or shield in front, so the heat is apparently not transferred forward or outward to the same extent.

There is definitely no discolouration of the front 'glass' (the transparent lamp cover).  I dried out the unit thoroughly by removing the sidelight bulb and using a hairdryer and plastic tube to blow warm air into the unit.  The front glass was crystal clear.  The condensation disappeared.  But after the car had sat outside overnight (and though it was chilly I don't think it rained much if at all)  the condensation was back....

In order to examine the headlamp unit fully - or to replace it with another one from a breaker - I will have to remove it. The presence of the screenwash reservoir and filler behind the LH headlamp means there's not much room to manoeuvre.  I really don't relish the idea of having to take off the front bumper panel as well as pulling the front wheel arch to do so, which is why I was looking for a simple how-to guide to getting the headlamp unit out. 

[LenT]

Sorry I can’t help with headlamp removal, Brian.  Maybe someone who’s actually done it might now see this post?  But I suspect that you’re right in thinking that will be the best way of finding how moisture is getting  in.

However, out of curiosity, I did a search for ‘Lexus IS300 headlamp condensation’ and quite a few posts on this site and the USA came up.

In the post I picked out two people mention foam filters behind a flap at the top of the lamp, which had become saturated.  Might be worth a check?

Another thought that occurred to me is the possibility that the bulb may not be correctly located and thus not fully seated in the lamp.

You don’t say if you’ve had the car from new, but I notice that some people with this problem do trace it back to what they call ‘fender damage’ which presumably means hairline cracks in the lamp after frontend impacts. 

 

[br1anstorm]

Thanks again, Len....  Yes, like you I had done a bit of searching online, and I had seen references to the "flap" and foam filters supposedly on the top of the rear part of the headlight unit.   But I cannot see or find any such flap or filters as I look at my car's lights.  I have also looked very closely at whatever photos and diagrams I can find online of the rear of the unit.  None seems to show or point to any such flap.  I ended up wondering if this flap and filter only existed on certain models - or maybe only on non-HiD systems (I think the IS200, for example has different light units).  If anyone reading this can point to a picture which shows this flap and filter, I'd be very interested!

I had also considered the possibility that a bulb may not be correctly or fully in place.  It is really difficult to access the bulbs, other than the side-light one which I have removed and refitted a couple of times.  I don't think any of the others have ever been removed or replaced.  A badly-located bulb seems unlikely to be the route for moisture to get in, though of course I can't rule it out totally...

Definitely no question of front-end impact.  I've had the car for almost 10 years, there was one previous owner, and I have all the history.

Tracing a tiny leak, a seal failure, or perhaps a hairline crack in the plastic (which I suppose is what I'm trying to do) is a real challenge!

[chaser@lexus250]

Hi there I've got a is200 but I modified to the is300 lights you can reseal them I've strip them plenty of times, mine has condensation and it's the silicon that seals the lense to the body of the headlight, you take them out and you stick it in the over at 100 degrees for 10mins and it heats the silicon so you can re seal them with more silicon, to get the light out the bumper comes off cause the hid housing gets in the way. 

Any questions just reply 

[Spacewagon52]

I have condensation in one of my headlights. No idea how you take off a headlight on a RX400h.