Always been the same here. Never any noticeable corrosion, yet after a quick clean, the box behaves for another 12 months or so. I've had that happen at least 3 or 4 times now; too many times to be coincidental, me thinks. Hopefully that's all it is in your case too +++

Hey Ho! The switch seems to be playing up.- at least I hope its still the switch! If I put it into sport the illuminated/highlighted "S" light goes out when I take my hand off the stick. If I press it back it lights up. I have also had one instance of the car sticking in first and I had to stop the car, switch off and re-start before it cleared. I also have had sporadic full PRNDS when engaging reverse. As I am about to put the car in for the lower control arms I think that I might as well get the F125 switch changed. Trouble is even the flat 10 pin plug versions seem hard to get hold of according to my garage.....

But if it IS the switch mechanism why did cleaning the connector seem to cure it? :Confused:

It probably just improved things a bit and disguised the symptoms for a while.

I don't see that acquiring the 10 pin switch should be any trouble at all - personally I'd go to TPS myself and order it, as you'll get a better price than the garage will and you can ensure you order it ahead of time so you know it's in your hands.

It may well be on backorder from Germany, but that usually takes less than 3 days to arrive to your local TPS - worst case scenario a week.

If Audi can't order it, it's a generic ZF part in any case I believe.

Thanks for that Adrian, The garage was getting me a quote through TPS and it appeared to be available on back order but I might see if TPS will quote me direct. To be fair my garage usually just charges me cost + VAT for parts.

You can get it online from Germany for 166.50 Euro + postage, if it is part number 01L919821B. The site is as follows:

http://www.carparts-pros.com/index.php

Cheers for that! I'll have a look. Despite the exchange rate its a good price. My garage quoted £175 + Vat thru TPS.

Out of interest has anyone tried pricing it up direct from ZF via the usual suspects - Chester, Mackies etc? Some stuff is cheaper from Audi, some vice versa so might be worth looking in to.

I was looking to do just that - Monday's job! +++

continuing on from my topping up transmission thread am still trying to solve my PRNDS/limp mode problem

my mechanic decided to 'pont' monday [ tuesday is a bank holiday in france ] to get a long weekend so now going wednesday

so ~I left the car outside in the cold , low and behold same problem in the morning including big clunk when changing gear ; been dry as a bone for days so no ingress of water

so drove a mile up the road in limp , turned around , stopped engine in park , restarted , no further problem !!! so back home and checked that the code had disappeared ; had it **** ; still 17090 /PO706/35-10 /implausable signal

as Alice said , curiouser and curiouser !

ps just discovered that there is a branch of TPS within walking distance of my home in southampton ...had a look at their website but they say trade customers only , how to get around that ?




so I have this fault except sometimes it puts the car in limp except when it doesn't ; the passenger mirror and reversing lights [ both controlled by the F125 ] operate all the time

I can't see past it being either oil level or F125; if it is the F125 how can driving a mile fix it but not fix the code ? why should it fix it anyway ? I can believe that if the oil level is a little low heating it woulld cause expansion but 1 mile ? how much would the temperature rise on a chilly morning ?

to be continued

If the car sets off without going into limp (ie moving it from P to D doesn't make it log a fault) it should work fine until you do move the selector again.

Switching off and back on might not trigger the fault, so as long as the DIS isn't lit up like a Christmas tree it will work as normal.

Fault won't disappear until fully cleared - it'll keep increasing the count on frequency.

TPS will sell direct in most cases - they just have to advertise themselves as 'trade only' so as not to annoy the dealers who are supposed to be the only choice for private punters. Some won't sell to the public as it's part of their lease terms.