I own a Audi a4 multitronic 2005. Recently i'v had the PRND flashing either individualy or all together and I think it's not going through all the gears and an intermittent failure to engage reverse gear, also the acoustic reverse bleeper has packed up. it's been suggested it could the gearbox ECU , ware do I find it ? please anyone.

I'm having a similar problem with my '05 A4 Multitronic with 75,000 miles on clock. PRNDS lights are all blocked out but not flashing (which I believe is worse). Car is driving ok after I had the EGR valve replaced by dealer at cost of £454. Dealer quoted me a further £1,077 to fit new gearbox ECU. Found a few websites that claim to be able to repair the ECU, best one seems to be www.BBA-Reman.com who quoted £169 +VAT + carriage. You do however need someone to take off and fit repaired ECU, had quotes ranging from £150 - £250 + £60 for 6L of new gearbox oil. However, I have been told by 3 independent garages that specialise in Audi's, BMW's & Merc's etc that they cannot be fixed, so I'm a little sceptical. To summarise the cheapest quote I've had for a new ECU fully fitted is from a garage on Tyneside (where I live) called Swift Motors 0191-2140056 who said they'd be able to do the lot for £860. Only bought car in February, absolutely love it, but sick as f**k at this unexpected cost which I can't afford. Had to take payment holiday from mortgage to cover the costs. Should have stuck with my old Ford Focus!! If anyone can offer any other tips I'd like to hear.

SOUND LIKE PROBLEM IN THE TRANSMISSION RANGE SWITCH. OR THE PARK NEUTRAL SAFETY SWITCH COULD BE GOING BAD.