super7pilot

Well we had the dreaded Check Engine Light come on (after 3 years of ownership & 34,000 miles) while on holiday on the Oregon coast followed by the DEF 10 start countdown. Went to Oreilly auto and they read the fault code (P229F) called MB of Eugene. they had the parts on hand and got me in the same day.

the service manager explained that the Sprinters have been having the same issues. he said that MB engineers found that the communication modules that both up & down stream Nox sensors are connected to had an out of spec run by the sensor manufacturer and when an individual sensor was replaced the two sensors became incompatible. And hence the repeated faults. The fix seems to be that they have to replace both sensors from the bad sensor run with certified compatible new sensors to then ensure that they communicate properly. New software was also installed.

Kudos to MB of Eugene for getting me in within two hours of calling them. Repair took two hours. On the two hour drive back from Eugene to where our motor is parked we experienced no more issues.

LesF

you should probably expect all your sensors will fail. I've replaced all of them after failures inside of 34k miles on my 14.

super7pilot

Really! And I should expect to die one day as well. Not to be rude. But please enough with the fortune teller type of over generalized nonsense.

Hugo L.

I think what he means is that contrary to some parts which may eventually wear, and others that you just don't expect to fail (I don't know... exhaust hangers, knock sensors, etc...), these sensors WILL fail.

I hardly see this as fortune telling, but rather an Achille's heel of these cars, which would explain why, when a sensor failed on mine, the dealer actually replaced both of them - I now know why.

super7pilot

Hugo, That might or might not be what Les meant. And I don't really care. There are plenty of other threads here in this forum about the certain meltdown of all GLK250's. He can go there to preach of the coming apocalypse for GLK owners.

I started this thread to show that I had found an explanation by MB that they have (allegedly) discovered why the Nox sensors have been acting up and that this might be usefull info for those in the future that get the CEL and 10 start count down. Or are having the issue again after a single Nox sensor replacement prior to this new development. As well as the great service that MB of Eugene provided me on very, very short notice.

LesF

Thanks for your reply Hugo L. I see you can read with comprehension of the issue. After replacing the sensors on all four cylinders on 4 different dealer visits with this car and two other visits for my first 250 then maybe I would have had a different view.

Apparently Super7pilot you don't get it, I'm talking from experience. Why did I buy a second GLK after the same problems with my first?




And no the sky isn't falling, you don't have to run an hide from the apocalypse.

super7pilot

I got it Les. I just didn't think it belonged in this particular thread. There are other GLK's suck threads to post yours as well as others displeasure. And that is fine.

I started this thread to say I had the sensor issue and MB said they figured out what the issue was. To that end. I posted that info so that other's can go into their MB service center with a bit of knowledge in case their particular dealer lacked that knowledge. Not to start yet another GLK's suck thread.

Hugo L.

I, for one, don't think the car sucks.

But as I said, I understand now why both sensors were replaced, and in case I thought about cutting corners and skipping on that, Les's post would educate me as to why I shouldn't.

I see it this way : in the end, both posts are somewhat complementary, even though that was not the intention you had starting the thread.

It's always a good thing to do a search with «Nox» or whatever and stumble upon, among others, this thread and know what can be expected.

gkhela

i got the DEF10 on my glk250 2013
mercedes dealer service replaced upstream sensor total cost with tax $1119,17
pretty expensive for 1 sensor hope the other will last longer since there are 2 on this model

Hugo L.

The heating element in my DEF tank got replaced, but intermitently my car now throws P203B and P203D codes.

As long as I can tho, I will keep erasing that code. No more expenses for the time being.

gkhela

my OBD2 reader 3 year old will not read the codes
can some one recommend a coder for glk250

andreigbs

Hugo: P203B relates to implausible signal from the Reductant Level Sensor, and P203D relates to Reductant Level Sensor Circuit High.
Maybe just keep the DEF level topped off? I wonder if perhaps there's a nicked wire post heater replacement work.

Ghkela: you can try iCarsoft for Mercs, or Carly with an appropriate OBD adapted, or what I use: BlueDriver.

gkhela

Thank you andreigbs
i will check these code readers