2007 - wont start and no dashboard.

[Rgrahamvox]

Hi,

I have a 2007 a3 dsg tdi, 200k miles, owned for a few years, that has this issue. A while ago, when I put the key into the ignition, everything would light up and work as usual including the dashboard. However turning the key to start the engine wouldn't do anything (not even attempt to turn over) and the dashboard would die. The needles would stay in position and miles would stay visible even with key removed. If I disconected and reconnected the battery the car would start fine. This happened about 4 times with weeks in between each time. Last time was last year.

However today, I put key in and the dashboard is dead. Nothing lights up or moves. Radio, heaters etc work but the windows dont (I noticed yesterday the drivers window was not working whilst driving the car but all others were). Also hazard lights work but it isnt making the usual click you can hear within the car I turn ignition on and the car fires but cuts out again immediately, again the dashboard has done nothing.

The battery has been tested and is fine and fully charged.

I dont know much about cars but I went and checked the fuses in the engine bay and by drivers door and they are all fine. I did however notice 2 wires badly corroded in engine fuse box (picture below), but I dont know what they are for.

I cant get my car to the garage until Monday, but even when I do, they arent great at electrics. Took them a week to find the source of a battery drain, which turned out to be a useless fuse in box for a feature my car doesn't have, drawing lots of power. This was about 2 years ago.

If it makes any difference, the car hasn't had underplates for a few years as they got snapped when we had bad snow, and it's obviously been quite wet recently.

If anyone could give any clues as to what could be the issue I would appreciate it. Also if anyone knows someone or a company in leicester which is reasonable price, perhaps has callout (as I cant start it!) that would be great too. As I said I'm not very good with cars, I think I saw a few threads pretty much describing this issue but couldn't find an answer, or perhaps didn't understand it!

Thanks everyone!

Edit to say I don't have a code reader, nor do i know anyone with one except my garage which I cant get to until monday.

 

[SootySport]

First thing to do is sort out that wiring to the fuse block. Disconnect the battery first then the corroded cables, spraying the terminals with penetrating fluid will help the nuts unscrew. Wire brush the cable ends and buy some new nuts.You need to get back to clean metal for a good electrical contact. The very rusty stud may snap off so try easing the nut of slowly and copious spraying of penetrating fluid.
You don’t need any diagnostic gear to do this.

 

[Tich]

check relays under steering as well

 

[Bloxham]

Check the ignition switch too.

 

[Rgrahamvox]

Thanks for the help everyone. Discovered the issue and back on the road today.

The instrument cluster had completely failed, having been a bit iffy for a few months. Found a company called ECU Testing on google, read their page and it described everything I had issues with in the recent past. I was slightly put off by their price (180+vat) but then discovered the same company on Ebay with a lower price (129 all in) for the same fix. Sent it off to them on monday, had it back today, put it in and car started instantly, everything working as it should. Brilliant, would definitely recommend them.

Now I just need to get a ****** code for the radio!

As for the fuse box corrosion that is my next task, I shall be doing it over the weekend.

Thanks again for all your input, very much appreciated.