The story begins in early March 2025, the first steps was to check if the car would fire up. Obviously the battery was totally dead and had to be replaced.
First thing first, replace the battery and try to start it. Result: lights came up in the car and upon trying to start the car, smoke started to billow out of the engine bay.
After replacing the alternator, the car started and moved forward and backward with a few red lights on the dash, main one was ABS second was traction control, the long process to clear all the DTC (Diagnostic Trouble Codes) started. As the car had sat for 9 years in all sorts of weather, luckily under a partial roof, it was not too bad, however the level of corrosion, especially in the ECU box located in the plenum at the back of the engine firewall, was major.
The main error was linked to the transmission and brakes system. Mainly caused by water ingress and connectors corrosion, I checked and dried the ECU box, protected it somehow from further water ingress – on a a side note – why would the engineers at Audi design a system that is right where most of the water coming from the windsrceen would end up flooding this plenum is difficult to understand. If so, make sure that the box is providing a very good seal, which is not the case; it merely is splash proof at best.
Other items that were found not working well or at all:
- Alternator shorted
- Windscreen wipers motors dead
- Wing mirrors folding not proper operation (since stopped working all together)
- Transmission (mainly corroded/unused contacts and ABS fault related)
- Rear brakes calipers seized
- Very very Mushy brakes.
First Start
The first start was epic. But I was far from “start up and go”, the next few months would be quite challenging, the first major step was to move the car from the car port as I needed to repair the roof. So I hired a trailer and planned the move back home.
The first main problem was brake pedal / gear shifter relation ship. As you can see in the video below the car dash sometimes failed to indicate what position the trans was in, the red icon did not light up but the car got in R or D or N no bother, then it beeped.
Second issue were the mirrors, they didn’t unfold…. If I manually unfolded them they stayed unfolded but power cycling the car made them fold back. Both mirrors could be adjusted up down left right but the “fold” option did not work, Me was thinking that I had maybe not been using the feature properly; the dial rotated all the way to 6 o clock and nothing was happenings.
Third issue was the sun roof, the button did nothing, all I heard was a “click”, I tried to help it by nudging it from inside but no luck there, subsequently found out about the manual override it was quite hard to get it unstuck. But doing so I managed to partially strip the 4mm Allen bolt, tip: don’t use an electric impact screwdriver, I also found the key to operate this roof in the back of the fuse box in the footwell.
I also thought that the drain holes of said roof needed cleaned as the footwells where quite soaked in. Especially the left hand one. turns out it wasn’t, more on this later.
Fourth, the steering wheel adjustment was not working. All I could hear was a clunk but nothings was moving, more on this later as well.
Lastly for the time: Windscreen wipers were also dead… I though the motor probably had seized and fuses had blown…. It was a bit challenging to say the least.
Before moving the car more seriously , I had to work on the brakes, most importantly lack thereof, the pedal was going to the floor and after a few pumps it kind of “prevented” the car from moving, not good enough, so only one thing for it, flush the whole system.
Went to Halfords and got a few bottles of DOT4 brake fluid, also bought a basting pipette to extract most of the old fluid out of the tank and proceeded to flush every single corner, starting from the rear left (furthest away from the master cylinder – Engine Running btw!) and so on. There were a lot of air in the lines, which made sense, after a good litre of new fluid in the system, that replaced very old and dirty fluid. The brakes were finally back to good old firm. However the ABS/ESP light were still coming on even after clearing the faults with my cheap Bluetooth dongle, I was not getting much details about anything so I decided to get a more advanced diagnostic tool.
Initially acquired an Autel, but it was still quite basic. So I returned it and got a Chinese XTool, which had a bit more features, still, had I known, I should have gone for a VAG Tool straight away; as it obviously IS the best system for these cars. But that [VAG] came much later, when i really decided that needed the thing to extract most of the faults accurately.
After clearing most of the faults, the ABS light kept coming was back on but the ESP one had gone (was flickering and I cleaned the abs pump connector seems to be doing the trick – for a while). I wasn’t at the end of the ABS warning light saga.