PNRD4321 (I thnk) problem

[awolfinsheepsclothes]

hi everyone
Started the car after work, pulled forward 10ft or so and left the car running in park while I filled the washer bottle and when I went to set of put it in d and the gear display was all red with no proper drive but reverse !
Turned it of to reset and it was ok then and worked ok on the journey home.
I'll check the oil level tomorrow and code read it
The mileage is 135k so may be due to nap it!
I had quick look in transmission section for the f125 symptoms and the only one I've found was Richierich37 and he doesn't continue his post after nov 2012
The kick down switch was turned of until 122k so I was hoping it had a easy life until me
The car only just started this morning due to drained battery could the low voltage have caused this?
Any advice cheers Dave

[Adrian E]

All lights on dis in red suggests limp mode - f125 switch is most likely but a fault code check will tell you for sure

[awolfinsheepsclothes]

Cheers adrian
I code read it today, unfortunately not vag com. the code On the launch was 17090 P0706 transmission range sensor circuit. F125 range /performance / sporadic
So you where right!
I removed the connector onto the gearbox and gave it a spray and checked the oil level. I'll see if it makes any difference fingers crossed.
Now do I dare do a oil change!
Cheers dave

[Adrian E]

What's the mileage and past box history?

If your plug clean up doesn't work it's about 150 notes for the switch - getting to it to change it would make it worth doing the oil and filter for the box if it's not on mega miles.

[awolfinsheepsclothes]

Hello the mileage is 135k and I've no evidence of any work done
So do I dare do a oil and filter change
Or get the sucky sqirty thing change
Or just change a litre of oil every time check the gearbox oil level so as not to disturb anything.
It seems a shame that no one has found a service schedule or oil that cures the 8 gearbox
Cheers dave

[Adrian E]

Might be worth grabbing a sample of oil and seeing how bad it is - if the miles have been done fairly easy in terms of load on the transmission it may still be worth doing, but the risk is you may dislodge something that leads to a greater problem if the oil is really gunky.

[The_Laird]

I had the F125 problems and just as you described. There are 2 different switches IIRC - one more expensive than the other (guess which mine was!).

And I had the sucky, squirty, pumpy oil change at around 100K. Felt better after that.

[awolfinsheepsclothes]

The ATF was pretty dirty really I'd love to change the filter and the oil. But after reading how others have failed after oil changes sometimes think I'd be better say draining 4-5 litres out and refilling a few times, say a week apart so I don't give the box a shock with new oil! And then there is the question of what ATF and do I get it from Audi or ZF.
Your switch was the most expensive one, like I bet mine is (FBG Box)
It's only done it twice when starting in park, so I could just always start in neutral?
Cheers dave

[Adrian E]

It's moving the lever that causes the fault code - mine used to do it getting it in and out of the garage as there's a bit of to-ing and fro-ing involved