Car has done 104k. 3 months ago ecu failed water damage we were told. Couldn't afford £1800 quoted to fit a new part so went for a used part and sent old ecu to them for data to be transferred. IVC (vw audi seat skoda specialist) at leeds fitted this for us. After few days rev counter stopped working returned to garage who said sometimes happens with used ecu's and basically just have to live with it. Fast forward 3 months to last sat - car left at airport for a week at meet and greet. Went to collect it told they couldn't get in to the car with key fob and when they eventually did wouldn't start. Flat battery we thought so jump started it. Sounded rough for 5 mins then ran fine the hour drive home. The rev counter came on on the jump start. Wouldn't lock with usual key so we thought key fob battery dead. Used spare key fob and locked fine.

Sunday - started fine had an hours fun and a couple more short ones. Used spare key.

Monday up for work started fine short 15 minute drive. Left 8 hours on return wouldn't start 1st time. Started 2nd time. Drove home 15 minute drive. 2 hours later went out to it failed 1st attempt then started 2nd time coil light flashing saying go to workshop.

Looked on here thought ecu might need resetting. Followed instructions on here disconnected battery etc 40 mins. Started fine when reconnected and left for 30 mins idle. Sounded normal didn't appear to be making the noises it should.

Turned ignition off and then tried to start it again. Dashboard just clicking and flashing.

Any ideas? Really hope this is not an ecu problem again. Don't think it's battery as ran fine all day Sunday.

Many thanks

I'd suspect the battery. Known to cause all sorts of issues when getting "tired".

Dave

Edited 12 July, 20169 yr by drefaldwyn

Yep, another vote for a new battery here.

 

All Superbs are fitted with under-spec batteries.

 

Get yourself a Varta E44 delivered to your door for less than £70...

 

http://www.ebay.co.uk/itm/Varta-E44-096-Car-Battery-77Ah-12V-780A-Quick-Delivery-/252223188704?hash=item3ab9ac6ee0:g:utwAAOSwzrxUtRsp

Aye battery worth replacing.

thanks Would the windows work if it was the battery?

thanks Would the windows work if it was the battery?

If the car is running, yes since the battery is being supported by the alternator.

No they work when the car won't start. Got jump leads on it now to see if we can get it going.

Had an Audi TT with a similar problem  and it turned out to be the CU which monitors the braking system flooding the ECU with errors. Replacement of some brake pressure sensors fixed it. I did go down the route of replacing the battery to no avail. You need to run diags on the car and see what is actually failing, a battery centre should be able to test the battery you have FOC but by all means buy a new better battery. Of course the replacement ECU could be dodgy but VCDS should give you some idea of what is really wrong.

I go battery as well then earth connection from battery to car body being slightly loose.

I'm voting with the battery guys as well.

 

This is almost identical to the symptoms I've had with a deeply discharged/well buggered battery.

The Superb (and MkII Octavia) are well documented for their very strange behavior with a dying battery.

 

Cars have been known to start fine so having the windows working could easily be a red herring.

Ours started doing all sort of all odd things when the OE battery was dying, including being able to open the windows with a battery that had no ability to turn over the engine. The dash was also dead as a door nail.

About 5 years is their lifespan . In the old days / pre ecu you could park on a slope and bump it until your battery was completely dead.

Vag seem to fit boy's own batteries , my 2015 vw bus keeps going flat , I had to jump start it with my old hyundai whose battery is about twice the size of the vw.

When my mondeo was playing up , the gauges would all read max including speedo abd rev counter, that was battery

Edited 15 July, 20169 yr by terrytowelling

I would be interested to hear what the fault symptoms were with the original ECU and how they managed to transfer all the requisite data out of a dead ECU.

But I hope a new battery plus earth connection check does the job.