I was driving home tonight, just cruising along and my rev counter and speedo die and I lose all drive. I manage to pull over (so power steering & braking ok) and switch ignition off and try to start the car up. Nothing! I take the keys out, put them back in, still no lights on the dash and no ignition. Dead. I pop the bonnet, everything looks ok. Get back in and now I get dash lights and it starts first time - no struggle.

I pull off, get to a junction few yards away and just as I go to pull off the same thing happens!

Putting the hazards on I try the ignition again, no dash lights & this time my hazards go off. Nice!

I do the same thing, keys out, bonnet open - try the ignition and it strikes up fine.

Slightly bricking it I decide to carry on my 40 mile trip home. Now back home and haven't had another problem. I've tried my fault code reader on it and it doesn't return any fault codes.

I did fill up with diesel (3/4 of a tank) & drove a couple of miles before this first happened, but can't see the connection.

Can anyone help me on this one please?

Edited 22 November, 201114 yr by magicpants

Something daft like a loose battery lead or engine earth strap perhaps? They can cause a sudden intermittent loss of electrics similar to what you describe.

I used to get this on a very decrepit Mini Clubman estate I owned as a teenager. Sudden loss of all electrical power, engine cuts out. Reach over and thump the back seat (battery was under the back seat on those) and everything back to normal for a while!

You really need a full scan with VCDS, but I would remove the battery, clean the terminals and refit. If the battery is more than 5 years old consider replacing as well.

Where are you getting your fuel? Is it always the same place?

I think the filling up with fuel beforehand is probably a red herring. The symptoms are a loss of electrical power, rather than just engine power as such. I can't see how poor fuel would cause the hazard warning lights to stop working for example as the OP describes.

I think the filling up with fuel beforehand is probably a red herring. The symptoms are a loss of electrical power, rather than just engine power as such. I can't see how poor fuel would cause the hazard warning lights to stop working for example as the OP describes.

What I can't understand is that my lights were still on, as was my aircon when it happened. So it wasn't a complete loss of power.

Could there be such a thing as my car key losing the key coding to the immobiliser?

I've been to work and back today - 80 mile round trip and all seems mine, but I'm still wondering if it will come back again. I will check the battery terminals later today.

It is possible for immobilisers to lose their key coding but its not common at all on VAG cars. When it happens on other makes it generally happens for good until the keys are coded back in by a dealer or someone with the necessary kit.

If certain items were still working it does suggest my theory on battery leads may not be correct, but I would still check them anyway to eliminate it as a possible cause. Voltage fluctuations can have weird effects on the electronics on modern cars. If there are no problems with the battery or leads a scan with VCDS is probably your next step.

+1.

Someone with VCDS near you could check for codes and errors.

Well after this initially happened earlier this week the car had been ok, until tonight.

Breakdown chap came out, tested the battery and fuses and still couldn't get it to fire up (thinks it could be relay related). So now have a dead car.

I'll get it into the garage and see if they can figure it out :(

try reseating all the relays in main fuse box.

try reseating all the relays in main fuse box.

With battery connected?

Prolly to be on safe side, make sure the connections look clean. There are relays in the cabin fuse box, try the same with those. Its worth checking the simple things first, you never know...

Update...

Skoda garage have been working on it all afternoon and after pulling half the dash out to diagnose the problem and have found the problem to be related to a relay somewhere around the drivers footwell.

Now not sure if the part & labour will be covered under warranty?!

Edited 28 November, 201114 yr by magicpants