Headlight Condensation

[mlsports]

Hi Guys

Any ideas on how to cure headlight condensation on a 2002 ML?

I asked MB how much it costs for a new rubber seal, they said they don't sell them seperarely and I'd have to buy new headlight units for £709 EACH SIDE!!!

How does the condensation get in there? A loose seal?

Any ideas on how I can stop it happening???

Thanks guys!!!

 

[merc convert]

Try removing a bulb and drying the inside with a hair dryer.

 

[Chas]

Hi Guys

Any ideas on how to cure headlight condensation on a 2002 ML?

I asked MB how much it costs for a new rubber seal, they said they don't sell them seperarely and I'd have to buy new headlight units for £709 EACH SIDE!!!

How does the condensation get in there? A loose seal?

Any ideas on how I can stop it happening???

Thanks guys!!!

http://www.mbclub.co.uk/forums/showthread.php?t=44545

Put all your lights on full and leave with engine running for 10-15 mins, this will clear it, or as above "Try removing a bulb and drying the inside with a hair dryer."

It's a design fault on many makes and models with large surface area headlamps. You need more air circulating inside the headlamp housing. As long as its just condensation don't worry ,unless its water entering due to a bad seal then the seals should be made water tight with sealant.

MB are talking rubbish and should stick to the script they have been given , the script below applies to all Mercs

Moisture in Headlamp(s)
Note : For Information Only!
If you receive customer reports in the above model vehicles moisture or water inside the headlamp(s), please
offer the following explanations.Surfaces fog up whenever they are cold and come in contact with warmer, humid air. An example of this is
the mirror in the bathroom. It often fogs up after showering because it comes in contact with the warm
humid air from the shower enclosure. The same thing occurs to the headlamps. Moisture or water on or
around the engine evaporates and this vapor condenses on the coldest surface in the surrounding area.
This is frequently the headlamps since they are frequently in contact with cold air or cold rain.
The headlamps have ventilation holes on the back. Without these holes, pressure would be produced when
the headlamps are switched on damaging the headlamps.
A malfunctioning headlamp can be identified as follows. As a prerequisite, the headlamp(s) must be fogged
up when the vehicle is brought into the workshop.
1. Is there a puddle of water inside the headlamp? If yes, the headlamp is malfunctioning and should be
replaced.
2. Does the headlamp show signs of external damage? If yes, the headlamp is malfunctioning and must be
replaced. This is not covered by warranty.
3. If there is only an appearance of moisture on the inside surfaces of the headlamp and there is no external
damage, the headlamp is then okay.
Note :If the owner complains of fogging but the fogging is not present when the car is brought in, then this is
normal and not an indication of any malfunction.
OK
ALLDATA Online - 1999 Mercedes Benz E 320 Sedan (210.065) V6-3.2L (112.941) - Lighting - Condensation in Headlamps
Clearing fogged headlamps and/or fog lamps.
1. Drive the car into the workshop and connect the exhaust extractor. In dry weather, this can also be
performed outside.
2. Start the engine and switch on the low beam + high beam, front fog lamps and hazard warning lamps.
3. Leave the vehicle in this state for 20 minutes.
4. Switch off all lights and the engine.
5. If the headlamps and/or fog lamps are completely clear, the observed fogging or water is normal. If not,
the headlamp or fog lamp is not functioning correctly and should be replaced.

 

[mlsports]

Condensation

Thanks for that! Much appreciated!

Both headlights have some condensation, but the two small round spotlights actually have some water in them. I guess I'll try removing the lenses and drying them out and then see if they refill.

Is there anything you can do to help seal them if the normal seal has become leaky?

 

[Chas]

A good silicon sealant for rubber from DIY or Halfords stores will do the trick

 

[panason1c]

Hi, I think that the condensation is considered 'normal', my ML headlights suffer from the same problem but clear themselves fairly quickly, i think trying to seal your h/lamps might worsen the problem.

 

[Quick Silver]

Check to see that the vacuum pipe is connected to the headlight (bothsides),the vacuum controls the height adjustment on the headlights.If no vacuum condensation occurs .If pipes are connected check by pulling one of the pipes off to see that there is a vacuum being pulled , should be around be around 10"hg , enough for the pipe to stick to your finger. A very cheap and easy problem to solve . Let me know the result.

 

[Quick Silver]

Headlamp Condensation

Check to see that the vacuum pipe is connected to the headlight (bothsides),the vacuum controls the height adjustment on the headlights.If no vacuum condensation occurs .If pipes are connected check by pulling one of the pipes off to see that there is a vacuum being pulled , should be around be around 10"hg , enough for the pipe to stick to your finger. A very cheap and easy problem to solve . Let me know the result.

PS ALSO CHECK THAT THE PIPES ARE CONNECTED ON THE BACK OF THE HEIGHT ADJUSTER AND ALSO THE VACUUM PUMP IF ITS A DIESEL OR INLET MANIFOLD IF ITS A PETROL ENGINE

 

[panason1c]

PS ALSO CHECK THAT THE PIPES ARE CONNECTED ON THE BACK OF THE HEIGHT ADJUSTER AND ALSO THE VACUUM PUMP IF ITS A DIESEL OR INLET MANIFOLD IF ITS A PETROL ENGINE

The ML headlight height adjustment is controlled by an electric motor on each h/lamp unit, not by vacuum.

 

[kenny murphy]

http://www.mbclub.co.uk/forums/showthread.php?t=44545

Put all your lights on full and leave with engine running for 10-15 mins, this will clear it, or as above "Try removing a bulb and drying the inside with a hair dryer."

It's a design fault on many makes and models with large surface area headlamps. You need more air circulating inside the headlamp housing. As long as its just condensation don't worry ,unless its water entering due to a bad seal then the seals should be made water tight with sealant.

MB are talking rubbish and should stick to the script they have been given , the script below applies to all Mercs

Moisture in Headlamp(s)
Note : For Information Only!
If you receive customer reports in the above model vehicles moisture or water inside the headlamp(s), please
offer the following explanations.Surfaces fog up whenever they are cold and come in contact with warmer, humid air. An example of this is
the mirror in the bathroom. It often fogs up after showering because it comes in contact with the warm
humid air from the shower enclosure. The same thing occurs to the headlamps. Moisture or water on or
around the engine evaporates and this vapor condenses on the coldest surface in the surrounding area.
This is frequently the headlamps since they are frequently in contact with cold air or cold rain.
The headlamps have ventilation holes on the back. Without these holes, pressure would be produced when
the headlamps are switched on damaging the headlamps.
A malfunctioning headlamp can be identified as follows. As a prerequisite, the headlamp(s) must be fogged
up when the vehicle is brought into the workshop.
1. Is there a puddle of water inside the headlamp? If yes, the headlamp is malfunctioning and should be
replaced.
2. Does the headlamp show signs of external damage? If yes, the headlamp is malfunctioning and must be
replaced. This is not covered by warranty.
3. If there is only an appearance of moisture on the inside surfaces of the headlamp and there is no external
damage, the headlamp is then okay.
Note :If the owner complains of fogging but the fogging is not present when the car is brought in, then this is
normal and not an indication of any malfunction.
OK
ALLDATA Online - 1999 Mercedes Benz E 320 Sedan (210.065) V6-3.2L (112.941) - Lighting - Condensation in Headlamps
Clearing fogged headlamps and/or fog lamps.
1. Drive the car into the workshop and connect the exhaust extractor. In dry weather, this can also be
performed outside.
2. Start the engine and switch on the low beam + high beam, front fog lamps and hazard warning lamps.
3. Leave the vehicle in this state for 20 minutes.
4. Switch off all lights and the engine.
5. If the headlamps and/or fog lamps are completely clear, the observed fogging or water is normal. If not,
the headlamp or fog lamp is not functioning correctly and should be replaced.

T

 

[kenny murphy]

Done all what said ,problem still exists.regards Kenny...

 

[kenny murphy]

T

Thanks 4 reply, bone all that,problem still exists....

 

[DREAMER NO2]

Old way is to drill a small hole in the light case so temp is same inside as out ,,.

 

[daveenty]

As the threads been bumped I may as well add to it in that the condensation is "perfectly normal" according to Mercedes.

I had it on my previous W212 and it still appears on the W213. According to the manual it's just a case of turning the headlamps on and letting the heat remove the moisture. With LEDs. Yeah, OK...

Another one of those quirks I just live with.

 

[John Laidlaw]

Indeed- I have responded the same elsewhere!

 

[Craiglxviii]

IT ISN’T A DESIGN FAULT.

It’s due to the laws of physics.

A headlamp is an enclosed volume containing air. That air contains water vapour. If there is a temperature differential between the air inside and outside the lamp that water vapour will condense either inside the lamp or outside it, also known as dew.

Lampmakers know this which is why every lamp has breather vents in the backs, or Goretex patches covering holes in the housing.

Dependent on the exact climatological circumstances of where your car is parked and on what day, you may or may not experience condensation in your lamps. Might be warm, might be humid, might be dry outside... and all of that might be different to the atmosphere inside your headlamp housing.

So, the only thing you can do is to affect the atmo in your headlamp housing to equalise it with external air. This can be done by:

Drilling holes in the housing (and fitting screw- in Gore tex one way plugs, or sticky patches).

Removing the lighting engine and blowing warm air in with a hairdryer.

Putting the lights on.

This is a problem we will see more of as LED lighting comes more into play; heat generated is less and goes backwards out of the housing.

 

[Craiglxviii]

As the threads been bumped I may as well add to it in that the condensation is "perfectly normal" according to Mercedes.

I had it on my previous W212 and it still appears on the W213. According to the manual it's just a case of turning the headlamps on and letting the heat remove the moisture. With LEDs. Yeah, OK...

Another one of those quirks I just live with.

Dave,

The other way is with heat soak from the engine bay. Turn lamps off, after a run and allow the not inconsiderable heat bulk of your engine to soak into the lamps...

 

[kenny murphy]

Hi, I think that the condensation is considered 'normal', my ML headlights suffer from the same problem but clear themselves fairly quickly, i think trying to seal your h/lamps might worsen the problem.

Hi tried hair dryer,,lights on full,4 half-hour,goes and comes back..

 

[daveenty]

Dave,

The other way is with heat soak from the engine bay. Turn lamps off, after a run and allow the not inconsiderable heat bulk of your engine to soak into the lamps...

What, you mean actually drive the thing?

 

[Craiglxviii]

Hi tried hair dryer,,lights on full,4 half-hour,goes and comes back..

The only other thing to do is carefully drill a 5mm hole in the housing of each lamp, to allow atmo movement.