2015 MB GLA 250 transmission issue

[SlavaB]

Hey guys, need your advice here.
I have this low mileage 2015 Mercedes (only 23k miles on it) that my wife carefully drives.
It does have some weird issue tho which happens not very often (like once a month)
It stops shifting gears, get stuck on one gear until you pull over and put it into a parking mode.
Then it drives normal.
I've brought the vehicle twice to a dealer but they can't reproduce it and there is no error code.
I even have a video from a dashcam showing how the car is revving up and not switching gears but they say it's not sufficient.
The video can be seen here https://drive.google.com/file/d/1dJLj4FHM2m8kRfE6Li8WuIchTPf_fYqD/view
Any ideas on what to do?

 

[WhyMe]

i would take it to a mercedes specialist and see what they say. plenty of them in the bellevue area

 

[Danno]

What would the dealer consider to be "sufficient"?
Maybe a dashcam view of the instruments showing the tach and gear selector?

 

[BMWTurboDzl]

Could just be a programming issue. Call the service department of another dealer to see if there's a TSB on it. If so, the fix should be free. My wife has experienced this same thing with her C-class. It's a rare, rare, occurrence.

 

[edyvw]

Yep, that has to be software issue.

 

[SlavaB]

Originally Posted by edyvw
Yep, that has to be software issue.


The dealer told me there is no software update for the car and as there is no errors they can't do anything.
Will take it to another dealer

 

[pezzy669]

Is there any remote possibility it is somehow getting bumped into manual mode while stopped? If it inadvertently gets knocked into manual mode it will hold 1st gear until red line then automatically upshift.

Reason I ask is I have done it in both MB's in my signature (C300 had center console gated shifter). The E350 has the column stick and paddle shifters so I am not even sure how that one happened, only thing I think is I was messing with the steering wheel controls at the light right before my engine was screaming along at 5k RPM in 1st gear with me wondering what was going on - then I saw the D1 in the cluster.

 

[SlavaB]

Originally Posted by pezzy669
Is there any remote possibility it is somehow getting bumped into manual mode while stopped? If it inadvertently gets knocked into manual mode it will hold 1st gear until red line then automatically upshift.

Reason I ask is I have done it in both MB's in my signature (C300 had center console gated shifter). The E350 has the column stick and paddle shifters so I am not even sure how that one happened, only thing I think is I was messing with the steering wheel controls at the light right before my engine was screaming along at 5k RPM in 1st gear with me wondering what was going on - then I saw the D1 in the cluster.


My wife drives it. While I'm pretty confident she doesn't do it accidentally, the dealer asked the same question so now I'm not 100% sure. Will talk to her to look at the dashboard if happens again

 

[dbias]

Does this model have the gear selector btwn the front seats or on a lever on the right side of the steering column?
I had a 2019 GLE 450, maybe?, as a loaner for a couple weeks and the gear selector was on a lever on the right side of the steering column and it drove me nuts. I hit it a couple times trying to one swipe the wipers lol. If it's there I'd think it's less likely bumped in manual mode than if it's in the center console like in my Jetta and A4, both of which I have bumped into manual mode by mistake.
Also she may be tapping the padel shifters on the steering wheel also. Lots of moving parts lol

 

[BMWTurboDzl]

Originally Posted by SlavaB
Originally Posted by edyvw
Yep, that has to be software issue.


The dealer told me there is no software update for the car and as there is no errors they can't do anything.
Will take it to another dealer



I would call the dealer. IMO,,,if the dealer network isn't getting a lot of complaints then MBUSA (MB AG) won't be spurred to find a fix.

 

[BMWTurboDzl]

Originally Posted by dbias
Does this model have the gear selector btwn the front seats or on a lever on the right side of the steering column?
I had a 2019 GLE 450, maybe?, as a loaner for a couple weeks and the gear selector was on a lever on the right side of the steering column and it drove me nuts. I hit it a couple times trying to one swipe the wipers lol. If it's there I'd think it's less likely bumped in manual mode than if it's in the center console like in my Jetta and A4, both of which I have bumped into manual mode by mistake.
Also she may be tapping the padel shifters on the steering wheel also. Lots of moving parts lol



It's a column shifter. Unlike the OP my experience as a passenger is that it feels like a dead spot where the transmission can't decide what it wants to do. It only happens after cold start.

 

[UG_Passat]

Instead of dealership, try taking it to a shop that specializes in Mercedes Benz. Depending on the shop, they may be more accommodating.

 

[MaximaGuy]

Believe they have a 4yr/50K basic warranty and the powertrain could be longer - take it to the dealership and maybe record it on the phone and show it.
These miserable dealerships are quick to point that it cannot be recreated...

 

[SlavaB]

Originally Posted by MaximaGuy
Believe they have a 4yr/50K basic warranty and the powertrain could be longer - take it to the dealership and maybe record it on the phone and show it.
These miserable dealerships are quick to point that it cannot be recreated...

Took it to the dealer twice, have all the records.
I do have an extended warranty so hopefully if smth gonna happen then it'll be covered.
I'm taking it to another dealer as well soon

 

[Wolf359]

Originally Posted by UG_Passat
Instead of dealership, try taking it to a shop that specializes in Mercedes Benz. Depending on the shop, they may be more accommodating.


It's a late model car that's under warranty. I doubt if any indy shop is going to be better at fixing it than an MB dealer.

When the OP goes to another dealer, ask the service writer to have a Master tech look at the car. They should have more experience on the matter.

 

[SlavaB]

Escalated it to the Mercedes USA.
Their technician looked at data and said the first problem is there is no data at all.
Transmission TCU is not recording anything so they've requested my dealer to change the computer first.
That will either fix the problem, or it will record an error if it'll come back.
Very interesting

 

[nthach]

Sounds like a TCU to ECM or CAN communications failure. The mechatronic(TCU) gets vehicle speed data from the ABS/ESP system and exchanges data with the ECM. But that would trip a CEL immediately.

 

[SlavaB]

Originally Posted by nthach
Sounds like a TCU to ECM or CAN communications failure. The mechatronic(TCU) gets vehicle speed data from the ABS/ESP system and exchanges data with the ECM. But that would trip a CEL immediately.


I'm not quite sure, will post their summary here as soon as will get it done. That's what a service advisor told me over the phone, but he might not know all the details.