Auto gearbox problem-need help

[ukcoupe]

I have an odd problem with my 'W'reg 2.4SE A4 Avant auto box. After driving for approximately 30 mins the gearbox locks into high gear and ALL the lights on the gear indicator in the dash light up. Stopping the car and restarting resets the ECU and the car behaves perfectly normally. After testing it appears to be a fault with the gearbox ECU, but as it's a random fault, I don't want to spend lots of money on a new gearbox ECU unless it will cure the problem.
Anybody got any ideas?

Cheers,

Chris

[STEWY L]

what "testing" exactly? did you take it to a dealer or an independant specialist?
if so,and they found it to be a fault with the gearbox control unit, why not believe them?
why spend time and cash trying to change other things? what other things are thier to be changed that would cure a fault with the control unit?
i would suggest a second opinion from a totally different reliable source,ie another garage.
regards,
stewy.

[pugville]

similar prob with my a6, if driving under 45 mph for a period of time it goes into limp mode as you described. Have changed MAP, MAF, Gear oil & Filter(This helped a little) but still have problem

[ukcoupe]

Well Stewy, the "testing" was the usual plugging in of a diagnostics computer and it was taken to two independent specialists, one an Audi specialist and the other an auto gearbox specialist. What was curious was that the fault code showing was P0605 which is a fault with the engine ECU not the gearbox. And of course I believe them, I was there. As it is a totally random fault, I wanted to see whether it was a fault with the engine ECU that was causing the gearbox to go into safe mode.

regards

Chris