[4themasses]

Check the overfill tank located on the passenger side of the firewall. This little resevoir is notorious for getting clogged at the bottom and overfilling with water into the cabin causing some serious problems....ask me, I know.

There are two metal clips at the top. Pry them off and clean out the drain at the very bottom. Check this often. If you don't and it plugs up, well let's just say this has cost me almost 2K in repairs. It can also freeze up in the winter so keep an eye on it. Every MB SUV has this issue.

 

[m5pena]

Check the overfill tank located on the passenger side of the firewall. This little resevoir is notorious for getting clogged at the bottom and overfilling with water into the cabin causing some serious problems....ask me, I know.

There are two metal clips at the top. Pry them off and clean out the drain at the very bottom. Check this often. If you don't and it plugs up, well let's just say this has cost me almost 2K in repairs. It can also freeze up in the winter so keep an eye on it. Every MB SUV has this issue.

Thanks for the heads up.

 

[pedra]

Air intake drain blocking

I found out the hard way last winter with my 2006 R 500 50,000 miles. After going through a car wash the intake flooded. Lack of a 2minute check cost me $3000. Of course MB don't advise owners

 

[Rodneyc77]

Anyone has a picture of what it looks like... is it in the engine compartment???

 

[4themasses]

Passenger side, upper area of firewall about where the hood hinge is. Big black box with a screen on top.

 

[vinr350]

wow! thanks for the heads up. will check it after work today. can we run a flexible wire to make sure the drain tube is cleared?

 

[4themasses]

Probably could. Might have twigs/sticks in there too. Just pop the two stainless metal clips off the top and the box opens up. Could also shine a light down in there to check as well.

 

[Vonhazelwood]

Thanks for the heads up. Mine was plugged.

 

[4themasses]

Thanks for the heads up. Mine was plugged.

Glad it helped at least one person! :thumbsup:

 

[thomgonzales]

I know this is a sad question. I located the box but have a quick question before prying open the box: Do the metal clips open from the front or the back?

 

[4themasses]

I don't think it matters. You should be able to get a flat head under it and twist one end or the other up. From what I remember anyway....

 

[thomgonzales]

Thanks. As you said, it pops open with a light flip of the flathead. I found a few leaves. Thanks for the advise and follow-up.

 

[4themasses]

Remember to keep an eye on it in the winter too. I've heard of it freezing shut/ice buildup in there and causng an issue. Maybe peek in there with a flashlite once in awhile or after a lot of snow has thawed off the car.

Cheapest preventative maint. on these!

 

[vinr350]

Checked. All's good. Thanks!

 

[pedra]

Does anyone know if clearing the air intake drain reed valve is included as a MB item in the scheduled service, and/or is in the later owner's manuals. This question is to US and Canada owners.
Despite the 2010 class action law suit in California on the subject of plugged reed valves, Mercedes Benz Canada do not notify owners, and in fact have told me that my plugged drain problem is to be expected. How do they expect anyone to find out until they experience the problem. I found out the expensive way with failed air blower controls, Yaw sensor and front SAM. It could have been very much more expensive to me personally and potentially others.
On a cold night early this year, well below freezing, I ran my R500 through a car wash to remove the road salt and grime. Unfortunately for me the intake drain overflowed and the damage to the electronics was only part of the story. I discovered this at highway speed when the windows suddenly fogged up. Anyone with an R500 knows that reaching the front screen is not possible when driving. At speed in the dark and suddenly with no visibility was scary. Fortunately for me and others on the road I didn't hit anyone else, but.... Then to find out the YAW`sensor was out, my "safe" vehicle was far from it.
Of course Mercedes Canada do not acknowledge that I or the car exist because It was first registered in Florida. Presumably vehicles sold by Mercedes Canada have a different air intake design or do they.

 

[BobbyHowie]

Wow, that must have been scary Pedra. Could have ended very badly indeed!

Think I'll be checking mine! Thanks for the very good advice!

 

[Soft]

On The same subject, check the spare wheel compartment under the black styrofoam, all the way down.
I found appr. 3 liters of water down there!!

 

[4themasses]

On The same subject, check the spare wheel compartment under the black styrofoam, all the way down.
I found appr. 3 liters of water down there!!

Where did that come from??

 

[GSD1]

Does anyone know if clearing the air intake drain reed valve is included as a MB item in the scheduled service, and/or is in the later owner's manuals. This question is to US and Canada owners.
Despite the 2010 class action law suit in California on the subject of plugged reed valves, Mercedes Benz Canada do not notify owners, and in fact have told me that my plugged drain problem is to be expected. How do they expect anyone to find out until they experience the problem. I found out the expensive way with failed air blower controls, Yaw sensor and front SAM. It could have been very much more expensive to me personally and potentially others.
On a cold night early this year, well below freezing, I ran my R500 through a car wash to remove the road salt and grime. Unfortunately for me the intake drain overflowed and the damage to the electronics was only part of the story. I discovered this at highway speed when the windows suddenly fogged up. Anyone with an R500 knows that reaching the front screen is not possible when driving. At speed in the dark and suddenly with no visibility was scary. Fortunately for me and others on the road I didn't hit anyone else, but.... Then to find out the YAW`sensor was out, my "safe" vehicle was far from it.
Of course Mercedes Canada do not acknowledge that I or the car exist because It was first registered in Florida. Presumably vehicles sold by Mercedes Canada have a different air intake design or do they.

Those grommets in the air intake should be removed as they freeze up and pool up water.

 

[4themasses]

Here is your fall reminder. Do it now or pay later!!!

My 02 CL55 even has this issue so it's not just the SUV MBs that have it.