91stealthes

Hello all,

A few months ago I purchased a 2012 GL350 CPO for my wife. There are a few items that I have noticed and wonder if anyone has any insight into them. I only drive the vehicle when we all go out and occasionally on the weekends, so there may be other nuances that I haven't found/heard yet.

(1) Sometimes the vehicle locks itself. I get out of the driver door and by the time I get to the rear to remove my child, the vehicle locks.

(2) When locking the vehicle (using the buttons on the driver front or driver rear) the vehicle will sometimes continue to lock itself. You can physically hear the doors locking and the horn continually beeps three times. I need to unlock the vehicle, either from the door or the fob and then re-lock. Sometimes I need to do this 3 or four times.

(3) When parking the vehicle in garage after driving, I hear a high pitched squeal from the front of the vehicle. Is this just the airbags deflating? A potential puncture in a bag? Of note, the car has never been on the ground the following morning.

(4) When doing yard work or such and I am in and out of the garage, I sometimes notice that a fan or compressor is running in the engine bay and upon looking in the vehicle see that the red light in the center of the passenger A/C control is illuminated. On these numerous occasions, the car had been parked for hours, sometimes even days. Is this normal to keep the air in the cabin fresh? If I open the door, the light turns off and the fan/compressor stops.

(5) On two occasions when in and out of the garage, I've noticed that the center odometer "square" on the instrument cluster is illuminated. No keys are in the car and it has been shut off for multiple hours or even days.

(6) At slow speeds I hear an electrical whine when hitting the accelerator. Is this a turbo spool, or an alternator whine? Is it normal? The whine could be prevalent at higher speeds, but road noise may drown it out.

(7) What is located under the driver side rear seat? The carpet had been cut out (and put back). I just question what the components are under there and why they would have needed to gain access...and I guess why they cut it out as opposed to removing the second row seats? Granted, I know it would take some time to remove, but this isn't a cheap vehicle either.

(8) As mentioned in another thread, my rear sunroof looks shattered from the inside, but looks clear from the outside. Photos available in other thread. Has anyone been successful with getting the rear panel replaced under warranty?

(9) The instrument cluster is informing us that both key fobs have low batteries. What is the typical life of the fob batteries?

Thanks for your information and expertise!

Cheers!

BlownV8

Take the list of concerns to the dealership. Your car has issues.

2010GL550

1. Not sure about this one
2. Sound like a problem
3. Our 2010 GL550 does the same
4. Our 2010 GL550 does the same
5. Not sure about this one either
6. I bet it is the turbo
7. Not sure, but I wouldn't be alarmed. The front passenger seat has the battery under it (as an example)
8. Good luck with this one
9. We get a couple of years out of the batteries. Perhaps that's causing some of your locking issues too.

Fourdiesel

6. check the power steering fluid level

sak335

4. This is the HVAC system doing it's normal thing. When the car is parked after the air conditioning system has been used, the car will blow fresh air over the heat exchanger to ensure it stays dry. In humid climates, many cars grow mildew when the A/C is used a lot and never dries out between uses. So they program the car to dry it out after use and keeps the A/C system from smelling musty.

9. I buy the batteries in bulk off eBay and it's cheap. I usually get a year out of them.

islandbeef

That's a lot of issues for a CPO, it seems they just put a CPO sticker on it and put in on the lot. Get it all fixed, pronto. And get a nice loaner, too.

alx

1. you have a short in one of the door handle buttons
2. see #1
3. if it still squeals/ clicks/ puffs 60 seconds later - you have an issue
4. your hvac blower control computer located in the blower case is failing. common. needs to be replaced
5. see #1
6. it is a pulley most likely. leave alone until it gets louder and easier to pinpoint.
7. dont worry.
8. good luck.
9. about 1 year

91stealthes

Thanks. I did before posting this and they weren't able to reproduce.

91stealthes

Thanks. I'm glad to see that other atleast had some of the same issues. Now the question is, are they normal? Being they tested these, I am assuming not.

91stealthes

I'll take a look at this tonight when I return home. Thanks for the suggestion.

91stealthes

Regarding #4, is this normal? The did a full A/C check on the vehicle. If this was normal, why would they investigate?

Regarding #9, thanks for the suggestion. Dealer replaced for free, but this is good for the future.

91stealthes

I was in a 2015 ML for 4-days (including Sat/Sun) while they looked into all the issues, so no issues there.

The vehicle supposedly went through the CPO process and I have the paperwork "documenting" so. Who knows.

91stealthes

Thanks.

Regarding #1, I think you are right and I think it's the driver door. I cannot use the driver door for "easy access" or locking anymore.

Regarding #3, I'll have to actually sit there and see when it stops. It's just something I noticed and wondered if it was normal. Being the car hasn't been on the ground, I'm not too worried. I have a 4-years and unlimited miles still remaining, so when a bag goes, it's covered.

BlownV8

Listen to Alx.

91stealthes

I wanted to provide an update as I received some information on some of the items. Thanks for all the feedback you all provided!

(1) Sometimes the vehicle locks itself. I get out of the driver door and by the time I get to the rear to remove my child, the vehicle locks.
The driver front Keyless Go handle completely failed and has been replaced.

(2) When locking the vehicle (using the buttons on the driver front or driver rear) the vehicle will sometimes continue to lock itself. You can physically hear the doors locking and the horn continually beeps three times. I need to unlock the vehicle, either from the door or the fob and then re-lock. Sometimes I need to do this 3 or four times.
The driver front Keyless Go handle completely failed and has been replaced.

(3) When parking the vehicle in garage after driving, I hear a high pitched squeal from the front of the vehicle. Is this just the airbags deflating? A potential puncture in a bag? Of note, the car has never been on the ground the following morning.
I was informed that this is the A/C motor removing any condensation on the unit and could run for up to 6 minutes.

(4) When doing yard work or such and I am in and out of the garage, I sometimes notice that a fan or compressor is running in the engine bay and upon looking in the vehicle see that the red light in the center of the passenger A/C control is illuminated. On these numerous occasions, the car had been parked for hours, sometimes even days. Is this normal to keep the air in the cabin fresh? If I open the door, the light turns off and the fan/compressor stops.

Nothing was notated on the paperwork, but I was verbally informed that this is to keep the heater box moisture free.

(5) On two occasions when in and out of the garage, I've noticed that the center odometer "square" on the instrument cluster is illuminated. No keys are in the car and it has been shut off for multiple hours or even days.
They informed me the cluster stays illuminated until timed out. I wish they would have looked into this more, as they should have definitely timed out by the time I noticed them.

(6) At slow speeds I hear an electrical whine when hitting the accelerator. Is this a turbo spool, or an alternator whine? Is it normal? The whine could be prevalent at higher speeds, but road noise may drown it out.
They could not duplicate it, but verbally stated it is most likely the turbo.

(8) As mentioned in another thread, my rear sunroof looks shattered from the inside, but looks clear from the outside. Photos available in other thread. Has anyone been successful with getting the rear panel replaced under warranty?
They indicated that from looking at the outside, it needs to be cleaned an polished. The car was professionally detailed shortly before going in for service and from the photos I provided in the other thread, you can see that it is nice and polished. I think they are trying to avoid this one.

BlownV8

Yeah, sounds like your dealer doesn't want to chase down the issues. I've never had any of those problems with my GL. Is there another dealer you can take the car to before the warranty expires?

cc4sc

Hate to be the bearer of bad news, but your listed issues are just the beginning...

I was in a similar situation a few years back. I bought a CPO 2010 GL350 in Dec. 2012. It had 40K miles and it was great for the first 6 months; loved the mileage I was getting on road trips.

Then little issues started adding up; windows won't open/close, doors won't lock/unlock, hatch wouldn't shut/lock, air suspensions go out, multiple oil leaks, not being able to put car in reverse, very difficult time starting/cranking the car to start, and a host of other problems. My last straw was when we broke down on freeway TWICE within 2 days of driving...family of 4 in the car. That's was that! Had to get rid of the thing.

Sorry to say the car is just not a well designed car. I was told after the fact that my car died in the middle of the freeway b/c a hose that supplied power to/from where it needed to had fallen off because a SINGLE screw that held the system in place had broke off. WHAT! A crucial piece being held together by a single screw??? That's what I was told and of course, this (and many other things) was NOT covered...even though the CPO warranty had not expired (wear and tear is not covered, so a broken screw led to hose breakage; one with "sensors" at that...cost me nearly $1,000 for just that single repair...because of a broken screw).

My only advice is, if you can bear all the nuances and quirkiness, then stay with it till the CPO warranty runs out...OR cut your losses and get maximum value while you can.

Ironically, the diesel model causes so much trouble, yet the diesel engine itself appears to be the most reliable part of the whole thing!

91stealthes

Yes, there are a number of Mercedes dealers within an hours drive of my home. Probably 10+.

91stealthes

Thanks for all the feedback. I am a little concerned that the vehicle has been in the shop 3 times (6 days) in the short 3 months that I have owned it. In my opinion, a CPO vehicle should not have two CEL come on, a faulty Keyless Go replacement, ad Blue heater replacement, and a leaking ad Blue tank. Granted, thinks happen and can be missed, but this seems like a bunch of issues in a short period of time. I will say that Mercedes service has been great though.

Regarding Warranty, I had purchased an additional 2 years of MB CPO, so as long as the pieces that fail are under warranty, I can most likely deal with the nuances. It is just frustrating.

I too am worried about the vehicle breaking down while on a trip with my family. The CEL illuminated (p20b8) Sunday Evening, and we got the vehicle in today and they tracked it to the ad Blue heater and also found the tank was leaking. Luckily both were in stock and replaced as we are heading out for the holidays. Then tonight another CEL (p2202) appears. I too don't want to become stranded.

I now really want to know what the modules are that are located under the driver rear seat being the floor was cut up.