CLK 350 Auto box stuck in first gear !

[Reggie-rock]

This morning I come out of a T junction with the engine fully warmed up and the auto box in Sport but it would not change up from 1st and seemed to be stuck in that gear. Realising there was a problem stopped, moved the selector from D to P and then back to D and then everything was fine for the rest of my journey.
As a precaution selected the Comfort setting as if it should happen again at least it would be stuck in 2nd being a bit more flexible until I find a place to stop.
Anyone had this and if so what cured it?
Thanks

 

[KennyN]

Anyone had this and if so what cured it?

I had exactly the same problem with my 2010 CLS last week and as we speak it is at MB in their workshop (under warranty).

I will report back later with their findings.

Kenny

 

[rifiki]

Had similar problem, geared at about 15 mph at 1000rpm.
£525 repair bill!!!!!!!!!!!!!!!

 

[KennyN]

Had similar problem, geared at about 15 mph at 1000rpm.
£525 repair bill!!!!!!!!!!!!!!!

What was the cause and what was replaced (electroplate) ?

I would like to have some factual information before I pick the car up later today.

Cheers - Kenny

 

[rifiki]

Have just dug out the bill, it's more £560.74
SCN code (what is that?) £72.00 Gearbox electrical plate £226.00
Plus oil,filters etc Hope that helps

 

[rifiki]

Forgot, labour £112.50 plus the dreaded VAT

 

[KennyN]

Have just dug out the bill, it's more £560.74
SCN code (what is that?) £72.00 Gearbox electrical plate £226.00
Plus oil,filters etc Hope that helps

The SCN part of the bill is to code the new electrical plate you your specific car , AFAIK.

Forgot, labour £112.50 plus the dreaded VAT

Cheers , thanks for taking the time to do that.

Just returned from the dealer and was told that after a scan of errors the only one of any significance was a faulty O2 sensor , there were NO gearbox errors at all. I asked why the gearbox was locked in second and was told that there are certain faults (engine or gearbox) that will lock the car in gear (to save damage) until the fault is reset or cleared.

With mine it looks as though the O2 sensor was causing emission issues as the car had just been started and it was that which put the car into limp home mode which seems to make sense as on the way to the dealer today I was getting 22 mpg from cold , on the return leg today (with a new sensor) it was back up around 28 , again from cold.

So it is a big to MB Giffnock , for the second time since I got the car in Dec of last year.

Kenny

 

[BlackC55]

A faulty O2 sensor wont cause that kind of gearbox fault. It may have just been a drop in voltage. I am very surprised it didn't throw a code. They do tend to easily.

 

[KennyN]

A faulty O2 sensor wont cause that kind of gearbox fault.

Would it cause the car to go into limp home mode and if so would that lock it in gear until the fault has been reset ?

Kenny

 

[BlackC55]

No.

 

[KennyN]

Would it cause the car to go into limp home mode and if so would that lock it in gear until the fault has been reset ?

Kenny

No.

Ok , ta.

I was only relaying what I was told by the dealers technician today and was in no knowledgeable position to debate what had been explained regarding the inner elecro mechanical workings of the gearbox. The car is still under warranty so they will be asked to investigate the fault and effect a repair if it happens again.

Kenny

 

[Reggie-rock]

Very grateful for all your replies so far but as mine has only had this fault once think I will have to wait until the problem becomes more frequent, as it is driving perfectly well since that one occurrence.

 

[rifiki]

About 1 or 2 months before the gearbox repair some times it would not change up. had to pump the loud pedal a few times to make it change gear.