Engine Management Light (no codes found) and DSG not selecting gear?

[georgekitchen7]

Hi everyone,

My Mum has a 2011 1.4 Polo with the DSG gearbox.

On starting it (after it being on the drive for 2 weeks), the yellow engine management light came on, and when you try and select any of the modes on the DSG, eg. Drive, Reverse etc., the “D” or “R” flashes, along with a flashing spanner, and the car does not move (it just revs, like it’s in neutral).

I plugged in my OBDII reader and no codes were shown.

Any ideas what this might be before I get it towed to a garage?

Here is a video of the problem if this helps:

https://youtu.be/Z8Yvy27jyU0

Is it a (dreaded) DSG gearbox fault rather than the engine, despite the EML symbol?

Huge thanks for your help!

[iichel]

Well, you must keep in mind that the engine, TCU (transmission control unit) and the ABS work together very closely.
If one of them is at fault, the others will suffer because they do not receive information to function properly and safely.
I would say here the TCU is at fault.

Your OBD2 reader probably only reads errors from the engine and not the TCU, even though the engine might throw a VAG-specific code to say 'gearbox isn't very happy today so I'm restricted in my functioning' ("function restricted due to errors in different modules" or "check DTCs of other modules on powertrain databus").

So, I'd suggest to get a VAG specific read-out tool or a more capable generic tool to read the TCU.
Odds are that it needs to be towed to a nearby garage anyway (clutch bad, hydrualics/mechatronic defective).

[georgekitchen7]

Hi,
That’s really helpful, thanks so much, much appreciated!
George

[georgekitchen7]

iichel,

Thanks again for your help. I now have the below codes from a better diagnostic tool - does this shed any more light on likely cause?

05998-00 Clutch 2 Opens Unintentionally P176E - Intermittent
01836-08 Gear 1 Not Selectable P072C Not A Plausible Signal - Intermittent
01851-08 Gear 6 Not Selectable P073B Not A Plausible Signal - Intermittent.

Many thanks,

George

[iichel]

I'd say either the clutch/gear linkage is at fault or (more likely) your mechatronic has some serious troubles.

[georgekitchen7]

Hi iichel,

Unfortunately thought that might be the case! Thanks again for your help.

George

[PoloDave75]

My GTI developed a gearbox fault a couple of weeks ago. There was a spanner flashing where it tells you what gear you’re in. The car was juddering at first, which it had been doing for about 18 months. I was told it was probably an electrical fault. Anyway took it to a local gearbox specialist and had the mechatronic replaced as the gearbox had 3 fault codes.

The car drove really well on the way home, but the next day it was awful. It wouldn’t engage in drive or reverse. Called the garage and they towed it. Upon inspection it turns out that the new mechatronic had a flaw in the thread that the accumulator screws on to. The rubber seal was shredded causing loss of oil and was leading to the clutches not engaging. Another new mechatronic unit was fitted at the garages expense and the car now drives like brand new. Although it did cost £1080 including vat.

[georgekitchen7]

Thanks PoloDave75, sorry to hear your tale of woe too!

In the end it went to a specialist transmission place in Birmingham where the clutch, mechatronic unit and selector forks were replaced for £2.4k inc VAT.

I found it hard to believe all 3 needed replacing, but when it’s in pieces in a garage, quite hard to argue!

Anyway, back to new condition now hopefully, so no big bills in the future (fingers crossed).