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DEF warning malfunction

52K views 21 replies 16 participants last post by  bsemion  
#1 ·
I've read that some folks have had a faulty warning "10 starts left" indicating more adblue needed. It will shut the car off if not cleared. I just bought a 14 GLK bluetec and, 250 miles later, the warning light appeared with a check engine light.

After having read reports, I called the dealer and the service writer told me the light meant I hadn't serviced the car properly and it needed fluid. I asked if it used 1 gal to 1 gal of diesel and explained the car was new.

After explaining to them what was wrong, they looked and a new fix//software upgrade was available for the first time today to resolve the issue. They kept car 1 day and I'm good to go.

If others have the issue, the fix is here!
 
#3 ·
There is a report on MBWorld.0rg of the adblue error reoccurring after the dealer had applied the software patches.

There is a poll over there too in an attempt to find out how many 2014 GLK250 owners have had the Adblue error and whether or not dealer has been able to correct it.

POLL: GLK 250 Model year 2014 faulty AdBlue issue - a poll - MBWorld.org Forums

If you vote, please add anote to indicate whether or not you had a successful fix or not. Thanks.
 
#5 ·
There have also been incidents of the Nox sensors replaced as part of the problem. You might have them check their function. I've suspected all along that it might have been a sensor issue rather than totally software. Had it been software, why aren't the 2013, the very same car, NOT having the problem with all else the same. If M-B got a load of sensors that were defective, that could be the reason only a limited number of owners are having the problem.
 
#6 · (Edited)
Last week I had the check engine light illuminate twice but no AdBlue warning. The first time the dealer reset it and checked the programming. The second time it happened they began to look at it in more detail and have asked for a factory tech to resolve the issue.

A new set of injectors is on the way. They are back ordered and I won't see them till mid January.

With the downtime I've had an opportunity to use a loaner glk350 and can tell you that the 250BT is hands down a much better overall package.
 
#8 ·
With the downtime I've had an opportunity to use a loaner glk350 and can tell you that the 250BT is hands down a much better overall package.

Headaches? No spare tire? More expensive trucker spec regular diesel? Etc? As much as I want the diesel version especially when I drove one in Italy and France, I don't think the US roads are ready for it?



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#10 ·
The emissions systems on all manufacturers Common Rail Diesels (CRD) are a "Check Engine" light waiting to happen. The emission system is very complex with a number of sensors, pumps, DEF Fluid heaters and Diesel Particulate Fluid that these diesels will never be as simple, reliable and long lasting as previous diesels. Add to the mix the use of Run Flat tires and your Mercedes service writer will know you on a first name basis. Also, the new Mercedes diesel is an aluminum block which will never last as long as the old cast iron block diesels.
 
#11 ·
To Sprinterman - I understand your frustration - and please understand that DEF is easily/easily contaminated with any exposure to non-complaint storage r transport containers - in exactly the same situation as yours a local "fleet" ran into major issues on their side when they decided to buy "bulk" and stored in a "fuel safe" steel tank.. DEF compliant containers are either specific DEF complaint poly or in metal tanks and nozzles only specific graded of low-carbon/low-nickel stainless steel are OK... even brief exposure to non-compliant metal - even the use of a zinc funnel - can contaminate DEF and cause problems in the SCR system (Nox, catalyst, etc)... literally the equivalent of 1 teaspoon of non-compliant metal can contaminate a 5000 gal tank of DEF.

DEF and SCR system is now a US Federal mandate for ALL diesel engines (on-the-road or industrial) between 176hp and 750 hp in the US since 2014. The Mercedes Bluetech system is based on Mercedes in depth experience - and with multiple failures such as you have encountered are indication of some type of DEF contamination.. usually metallic in nature.

Also please understand that the 2013 Sprinter powerplant is the 3L V6 - and here in the GLK is the 4 cyl turbo.

I am NOT saying the DEF/SCR system in all vehicles is perfect - however what I am saying is your SCR problems (Nox, tank, catalyst) ALL point to a DEF contamination problem - and once a vehicles DEF and SCR has been seriously contaminated contaminated - yes - it is a b*tch getting the contamination flushed and especially getting SCR system back to spec.

I have seen Sprinter commercial operators fill 5 gal fuel cans with DEF - hey,DEF is relatively safe, put in a metal gas can - thinking "why not" - 5 gal "jerry" type cans can be strapped into the back easily - and EXACTLY the wrong thing to do.

DEF is relatively chemically stable - meaning it doesn't rust/corrode a "steel" container or metal funnel - but that metal certainly contaminates the DEF like crazy.

I am trying to be helpful here...
 
#13 ·
Contamination does not explain the myriad DEF system problems being encountered by GLK 250 owners who have had DEF replenished exclusively by MB dealers. I just had my second CEL (no starts remaining indication yet) in 7200 miles on my 2014 250. The first time a NOX sensor was replaced. No way would I keep this car beyond warranty unless this problem is solved. Yes, I too see a class-action suit on the horizon. Luckily, I still have three years and 40K plus miles warranty remaining for MB to solve this serious problem.
 
#14 ·
This problem has occurred not only for GLK Mercedes but in their Sprinters dating back to 2008. It also is occurring in other brands using DEF. You can read about the issue in Dodge diesel forums.

While getting my A service several months back I asked the service manager about this issue. He referred me to an adviser who apparently has been designated by MBUSA as the guru to repair the issue. Apparently Winnebago using Sprinter chassis experienced the problem in vehicles being transported down the I-80 to California from the factory in the midwest. This dealer is right on the I-80. All these problems with the vehicles moving west were then referred to him and to this dealer. In discussing it with this adviser he told me the problem can be a combination of several minor items, the DEF level sensor, and a bad NOx sensor being the usual culprits. A malfunction in any of these triggers the required shut-off in the software therefore requiring a software reset, along with a repair of both the other sensors, the DEF level and one of the two NOx sensors.

The real problems seems to be incompetent and inexperienced service personnel. About the time I looked into the matter a frustrated owner with a problem in his GLK complained about it on one of the forums. He had been to several dealers who failed in any solution. He went to the dealer I had mentioned to him and his problem was immediately solved. I understood they replaced both the sensors and reset or updated the software. My concern is that I travel in areas where dealers are few and far between, or non existent but luckily I've not experience the problem. I also understood that there is a alert in their LI bulletins covering the issue and the solution.
 
#15 ·
I own a 2013 ML350 Bluetec, at around the 14,000kms mark the yellow check engine light came on and then the adblue 10 starts remaining warning. Took to the dealer and they said it was a software issue and claims to have fixed it. Got the car back drove around 150-300 kms and they light and warning came on again. Took to the dealer and is currently still sitting there. They said they contacted factory/ headquarter in germany to see whats up with the car, they are still waiting on a word back. They said mechanically there seems no issues its some sort of software glitch they are trying to solve. The car has had its yearly service at the dealer with adblue refills. Will update as it progresses. Is any one else having these types of problems?
 
#16 ·
Are you aware this is a GLK and not an ML forum?

Different engines in those two models.

The problem has occurred across the board with all diesels, Mercedes and others, including domestic. The problem in the Sprinters that use the same engine you have, has been occurring since 2008. It's usually an issue with technicians who don't understand the issue and how to fix it. I was told reprogramming of the system is involved but the main issues are electronic in the NOx sensors and DEF level sensor.
 
#17 ·
Got my car back today and the dealer contacted germany to solve the problem, they apparantly said there was a problem with the enitre ecu system and they replaced it. I always take my car to the dealer at MB Vancouver to get it serviced and I hope they know what they are doing considering they are the flagship dealer here in BC.

Who told you about the sensor issues you mentioned?