usulbaggins

Hello folks,

Newbie here.

Have a 2016 GLC which overall I love. Lots more personality than the various Lexuses I have owned. However, do have one issue that seems to be getting under my skin.

Every time the car is driven after its been standing for some time (like overnite), so the engine's cold.....about half a mile from the start point, there is a gentle clunk from behind the steering wheel/console area. It does it almost about exactly at this distance. It does it only once and then drives perfectly all day long. Does it in all drive modes. Has nothing to do with road conditions or imperfections. I live in Houston where its been 80 degrees lately....so can't say its been cold. I would love to take it to the dealer but its a nuisance of a problem to replicate since it only does it when the car's not warm.

As far as I can tell, no gear shifts are taking place at the exact moment when the noise occurs. Any ideas? Is this something concerning?

Oh, and I have given up on Keyless Go. Does not work about 75% of the time. Works reliably when the key is in direct line of sight to the starter button area. Dealer says my other key - an Audi - is interfering. Who knows. Just annoying. Have changed batteries etc. No improvement.

I also have the screeching brakes, juddering wipers and have experienced the tire "crabbing" once in cold, wet conditions. The car is a 2016 RWD with 18 inch tires. I consider them part of the car's personality.

Thanks for any suggestions you might have.

TheSpooky

In the past few days (since A service-may be just coincidental), I noticed something very similar. It sound like as "bird's feather flapping". My suspicion is it is something to do with air conditioning as it often coincides with the beginning of air circulation. I will report as soon as I learn something more definite.
Agree, taking it to the shop is waste of time due to lack of reproduciblity.

George in KG

My Keyless Go works 100% of the time regardless of whether the fob is in my jacket pocket, pants pocket or down in the door pocket. The fob is kept by itself with no other keys.

Have you tried separating your key from anything else to eliminate the possibility of interference?

dieseldoc

Other keys can interfere. On opening and locking the car need to be careful of hand position. It can become confused if part of hand is behind handle and part is in front of handle.

usulbaggins

So I just drove with the climate completely turned off. No luck. It did it again. Wife heard it too. Seemed fainter, maybe because the car was not completely cold. Seems to be coming from some place around the steering wheel area. Are there pumps/bushings in that area that can go bad or something?

As for the keyless, I will try separating the fob from the rest. Hand position is definitely not the problem. If it is interference from the other key, how do those of you with spousal vehicle constraints handle the second key? Keep them separate?

dieseldoc

We keep keys separate. I have had no problems with keyless go. The cars are full of electronics that make all kinds of noises.

usulbaggins

ok, so I can get pretty silly once I set my mind to figuring something out. This is one of those moments. So, I went out again and made some serious progress....

1. Separated the Audi/MB keys. Left the Audi fob at home. Keyless go worked flawlessly every time. So, that's that.

2. This is the more interesting one. The clunky noise I talk of has nothing to do with the car being cold. I can reproduce it consistently now. The trick is to turn off the car completely, step out and lock it. Then get in, start and drive again. The noise happens about when the first time the car shifts from D4 to D5 in comfort mode. Drives flawless thereafter. If I just stop the car, turn it off, restart and drive (without getting out or locking).....it does not happen. It seems that locking the car resets some system which is unhappy the first time it is called upon when the car starts all over. I hope that makes sense. Does not seem to be a mechanical issue or it would happen all day long. Any ideas? Something needs to be reprogrammed? The dealer recently applied some update for COMAND. Wonder if that did something since I do not remember hearing this before that.

Anyhow, if I can reproduce it.....I can go to the dealer.

usulbaggins

Let me ask another question....

For the life of me I cannot figure out how to get the GLC to display if a door or hatch is ajar when it is switched to D or R. It does give me a warning but only once the car is moving and, even then, not which door is ajar.

Every car I have owned in the last decade displayed icons about doors/hatch that were ajar. Is there a setting someplace I am missing?

dieseldoc

There is no indicator. It will tell you door is open if car is in reverse or drive in multifunction display.

ItalianJoe1

The warnings don't pop up until the vehicle moves, but it should say "shift to P" or something of that nature if it's in gear and the door is open, this may be only for the drivers door.

Jetfuture

Baggies,
I have noticed the "clunking" noise too. It happens consistently once passing about 30mph as I leave my neighborhood each morning. The sound comes from somewhere left and below of the steering wheel. Perhaps above where my left foot rests.

Because it happens at the exact same time while leaving my neighborhood and passing about 30mph, I believe it is something that is arming. Perhaps something to do with the brakes or another safety feature?

One thing is for sure, this car has a lot of electric motor noises. I think one should only be worried when they never run or never stop.

usulbaggins

This is exactly the noise and the scenario. Actually, I just came back from the dealer. We were able to reproduce the noise in my car with the shop foreman sitting next to me.

Next we tried to find another similar car on their lot to crosscheck against. Since there was no 16, we drove a 17. Guess what? It does the exact same thing. Now everyone's flummoxed.

Anyhow, he intends to look into it. Nonetheless, I know I am not imagining it and my car is doing exactly what other RWD GLCs in Texas are doing. So, I can live with that.

Unrelated note: Wrapping my Audi key in aluminum foil stops or weakens the interference enough to make keyless go work flawlessly. Now I need to go find a RFID blocking key fob wallet.

Yes, I know I need to find better things to do in my life instead of chasing car gremlins.

dieseldoc

I am in Dallas. I have a 2016. Will see if mine does it. I will pm you. Mine is currently at the dealer being serviced.

easternshore

[QUOTE=Jetfuture;7049890]Baggies,
I have noticed the "clunking" noise too. It happens consistently once passing about 30mph as I leave my neighborhood each morning. The sound comes from somewhere left and below of the steering wheel. Perhaps above where my left foot rests.




Same here. I wondered if it is the ABS. I use to hear that years ago with a car that I had and that was the explanation that I got from the service department.

dieseldoc

Have dealer check Struts for noise if it is consistently there especially over bumps.

blizzard12

ABS second self check on my older Volvo happens at 15 mph and is quite noticeable (even the owner's manual mentiones this, first one happens at startup).

On my C300 it happens at ~10 mph and is hardly audible. Nothing else kicks in above that speed.

TheSpooky

As I was getting "Squeaky Brake" fixed, I asked SA to look into this. He seemed to be aware of this issue but wanted to re-produce the issue before attempting a fix. Ask to leave the car overnight with them so that they can check in the morning after a cold night. And bingo it reproduced.
Fix: Remove side vent and apply special lube to marked areas as per LI 68.10-P-058924

jeffzou

I had this "clunky" noise issue as well. It is a known defect. My dealer (MB Of Laguna Niguel) immediately fixed it. Here is their write up:

Noisy air deflector WP Tech 2240. Perform repair per LI Document LI68.10-P-058924. Apply special lubricant to air deflector shaft in housing.

That was this past Monday. No noise since then. It was resolved during my Service B at 20,000 miles.

FYI

Jeff

pjw1967

If you type juddering in the search field on this site, your computer screen will dim as the multitude of posts load up. There is a some controversy about what MB uses to deep clean a windshield. I have personal experience using original Bon Ami. Available at ACE Hardware. Picture below. General Motors actually repackaged it under their own part nbr for this condition.

TJGLC300

Does the Audi key fob allow you to turn it off? The Mercedes can be turned off by pressing the lock button twice rapidly in a row, saving the battery.

Seems like it would be easier to turn off the Audi key if you can than using an RFID key fob wallet.

ItalianJoe1

There is a bulletin about cleaning the windshield, there is a specific cleaner we use, it's rather strong.

The root cause is the wiper blades, they just suck, and MB doesn't seem to care. We replace hundreds under warranty, polish windshields, adjust wiper arms, etc. I bought a set of new wipers for my old CL, and they now dance across the windshield. Its not like my 15 year old car now suddenly needs a special cleaner on the glass. It needs wiper blades that don't have whatever these new ones have in them.

easternshore

Is this necessary? Does it really need to be lubricated, or is it just to get rid of a slight annoyance?

TheSpooky

Depends...
I thought, if not resolved early, this may lead to mechanical failure. Lube is an easy fix and MB is willing to do it. If it comes back I can always seek a fix.

ItalianJoe1

Only if it makes noise...

It's just the adjuster motor for the far right air flap. The bulletin is so they don't get a bunch of techs replacing the motor when all it needs is a little grease, it's not a bulletin like a recall. There are thousands of bulletins related to the easiest, most direct way to fix common problems, to help get the cars fixed right the first time and minimize comebacks.