2014 GLK 250 bluetec AdBlue warning
So far, since December, my car has been in and out of the shop for engine light issues that were initially traced back to the fuel injectors, which were replaced with the fuel lines after 4 visits and 10 weeks of waiting for parts. Next, one of the N02 sensors was found to be bad and subsequently replaced. Next failure was the dreaded adblue warning while the dealer had the car. When it rains it pours.
A day later, after getting the car back, and we return to the injectors with the same error code. Things were so bad that the dealer with consultation at the factory wanted to buy the car back because they couldn't fix the problem. I started to look for a suitable replacement but found this model is very difficult to find, new or used, optioned to my specifications. (I absolutely hate the black interiors as they look cheap to me.)
Both the dealer and factory took a last chance at resolving the issue and according to my service adviser, reprogrammed the CDI module with newly developed code. That fix extinguished the engine light and the engine was again running normally.
During this time my dealer provided a loaner Mercedes (from Enterprise)for the entire time my car was in the shop. They were in contact with me on a regular basis, and treated me as a valued customer.
Last edited by LesF; Mar 21, 2014 at 01:04 AM.
However, there are a few gripes that I have about this vehicle.
1) The height adjustment release button is missing on the Neck-Pro on the driver's side. So there is no way that I can lower the headrest (it's at the highest position now). See pic below:
https://drive.google.com/file/d/0B2P...it?usp=sharing
2) The air lumbar support seems like it doesn't hold the inflation. It deflates to about half of the hardness within 15 minutes with me setting on the seat.
3) There are unusual rattling noises coming from the rear of the car when driving over uneven roads. It seems to be coming from underneath the rear bumper around the chrome part and the heat shield above the Adblue reservoir.
Aside from these issues, everything else seems to be ok for now.
Last edited by sklok; Mar 21, 2014 at 02:35 PM.
The passenger side has to be adjusted manually with the release button.
Last edited by BMIKE622; Oct 14, 2014 at 12:06 PM.
CEL cause: 54065 On-Board power supply voltage maintain (when checking/testingand troubleshooting) 904083
540991 Control unit software: Install
540992 Control unit: software: Install
3027 short test codes P2BAAFA,P13E3F00,P12E3 in CDI hooked up charger
Performed software update and coding. Per LI 49.10-P-058243
AD BLUE warning:
470643 Separate parts for adblue system as per fail code check
90483 W AdBlue
3029 See job A for initial repairs. Had to go to special procedures in CDI and reset message. Had to top off Adblue, then had to go to SCR and reset.
I have 10,025 miles on our GLK250. We love the comfort, handing and performance. Hate the dependability. I'm a diesel fan, but I'm being to wish I had stayed with Subaru. I know there's no comparison in the comfort, but Subaru sure beats Mercedes in dependability.
At 9,500 miles I added Bluetec, approximately 4 gallons to the bottom of the filler neck, and made an appointment for the first service. At 10,005 miles the wife called with a check engine light, I told her not to worry it was going in for service the following day. When she arrive home she also had the 10 more start warning. To this point no add Bluetec message.
I check forums, saw were someone suggested the Bluetec had to be completely full. So I
filled it completely, to the top. Then the forum said take it for a drive, I did. Also saw post that said turn the key on, don't start the car, and wait 30 seconds. This would reset the warning. Only thing I accomplished was waste my time and waste a start.
This morning on the way to the dealer the Add Bluetec light came on. While my wife was dropping off the car, a driver delivering a new Motorhome, on the Sprinter chassis, was having the same problem. Who pays for wasting his time? He's stuck sitting around the dealership instead of making his delivery on time.
I think Mercedes has got a problem, with the number of forum posts here and on other websites, the should be a recall. Who wants to take a car on the road trip knowing a faulty warning light can leave you stranded? I can only imagine getting stuck in the middle of Montana, no dealer for 100's of miles and the car won't start because of false warning light. How can an upscale Auto Manufacture build and sell a car that will tell you to add windshield washer fluid, when a tail light's inop, but can't tell it's got plenty of a required fluid? To make things more ridiculous, from what I've be told, the Bluetec fluid is strictly an EPA feature, it doesn't effect the engine at all. The fluid is actually injected in the exhaust system down stream of the engine. There should be a way reset the system when there's really not a problem.
At this point I WOULDN'T RECOMMEND anyone purchase a GLK-250 Diesel (Bluetec).
The Best of Mercedes & AMG
One thing I'd really like to know is if this happens again, and I'm in a remote location, is there any way to circumvent the limit of starts remaining? I personally think its ridiculous that for the price of these cars, they would put such a potentially problematic 'feature' in the software.


Bear in mind that thousands have these BlueTec cars without problems. Those without problems don't post. You see a disproportionate number of problems from the few frustrated users. Certainly understandable. Someone counted something like 8 or 10 problems in a poll after thousands of 250's had been sold. I happen to be one, of many, who have not had a single problem of ANY type with mine @ 9000 miles. NEVER a problem in the E350.
Frustration of owners with the problem is obvious and understandable but the many satisfied users don't post. If the issue is a major problem to an owner, get rid of the car and go back to a 'ricer'! Toyota, Suburu and Honda make good cars, and there's always Kia!
I'm glad the US spec has the Adblue system as it helps with the exhaust smells typical with diesel. Here in Germany there are lots of diesels and all of them smell funky compared to MB's Bluetecs.


It may not be a safety issue in and of itself, but limiting starts when someone very well could be 100s of miles from a dealer is a concern to me. My ’10 starts remaining’ fell on a Friday afternoon so it was only an inconvenience for me not to be able to use the vehicle over the weekend. I regularly travel for days at a time through remote areas (Wyoming, Nebraska etc.) If I were on the road far from home and a known glitch in the software of my 55k vehicle prohibited me from driving it, or changed my plans, I’d be pissed regardless of who is to blame.
I don't think it’s unreasonable to expect MB to reach out to GLK owners who have early 2014 model year builds and offer a preemptive software update before this happens. If they're capable of a software fix, then they're capable of isolating the issue and identifying which units can/will fail.
I can’t speculate how widespread the issue is any more than the next guy. It was interesting to me that 15 seconds into our conversation, the dealer knew exactly what the problem was and how to fix it. The person I spoke with admitted they’d had a number back in for the same problem. 8 out of thousands sounds very fishy to me.
The Best or Nothing… right?


I think that IF we have any disagreement, it's the natural one between someone with a problem and someone with none.
Well, we can agree there I assure you. If software were perfect, I'd have a whole lot more time on my hands.
I expect more from a brand that professes to be above the fray. While I don't expect perfection, I do expect better than a reactive response when in my experience, I'd bet MB has the data they need to identify which units are defective and proactively fix this issue before it becomes 'alarming' to the customer. MB should know which models had the problematic software/hardware config and isolate proactive fixes to just those vehicles.
There's nothing alarming about suggesting a customer come in for an update based upon their build date/model etc. See above. Expensive? Maybe. Sometimes doing what's right for your customer isn't always the least costly option. If I wanted cheap, I'd have bought a Kia as you suggested another poster do. I for one feel I paid for something better. Maybe I shouldn't.
I'm afraid software that doesn't work is a quality control problem. Do you want to fly on a Boeing Airplane with a software problem? I don't want to drive a car with a software problem, I didn't spend $50,000 to be a test pilot for MB.
Also those who think it's only effecting a few folks should consider only a very few MB owners are on this forum. Also many MB owers are older and either don't own a computer or think it's only for forwarding emails. Usually the same email they forwarded weeks ago, only now there's even more attached addresses.
I bet there's a lot more folks with 250 Bluetec problems than we're seeing here.
At least Mazda has the good sense to keep their new US diesel off the US market until the figure out a fix for their problem.
Picked up the car today. The service manager said had no bulletins from MB concerning the Add Bluetec messages. He claimed that the tech's worked over time last night trying to figure out the problem. They did the engine update everyone talks about, which cleared the Check Eng light, but not the Bluetec message. Then they did an exhaust system software update which cleared the Bluetec message. We'll see. It's hard for me to believe MB hasn't informed dealers of this problem. Service manage said the dealership has only sold 4 GLK250 Bluetec's, so far I'm the only one with this problem. Hope that's the end of it!
Last edited by toogrumpy; Apr 8, 2014 at 09:24 PM. Reason: update
If we know this error isn't actually a serious problem, and more of a software annoyance for compliance with emissions standards... why not disconnect the negative battery terminal for a couple of hours and then re-connect and see what happens? This should clear the ECU.
I'm not suggesting this is an actual fix- more of a work-around for those who can't get to the dealer or what have you. If you do try this, be prepared to lose some personal settings, although I'm not sure what will "for sure" be affected - probably memory seats, radio stations, power lift gate settings, etc.


It has worked on my Sprinter Motorhome for other issues.



And yes, Canadians are having this problem too.



