Good morning,

so, our 08 Octavia has been utterly reliable for many years, hence my lack of activity here! Today it has let us down. Yesterday it ran fine, as usual, with no issues.

Went to use it today.. engine fires up instantly as always, then dies straight away and will not run.

Multiple dash lights are on - ABS, traction and a flashing hand brake light with a beep.

Your thoughts would be appreciated.

Thanks

Tim

Cheapest possible place to start and rule out:

Immobiliser: lock and unlock the car and try again.

Some cars if you take too long after getting in before starting the immobiliser kicks in and won't reset until you reset it that way.

I always think of general weirdness, especially random dash lights, as being a battery issue.

Does sound like the imobilser kicking in. Try another key if you have one. It may be either the transponder chip in key or the reader coil in ignition thats failed. Had same problem on 1.9tdi BXE Seat. Used bad key and in my case imobiliser stuck on.

Alasdair

24 minutes ago, JamieH86 said:

I always think of general weirdness, especially random dash lights, as being a battery issue.

+1 battery likely

Thanks for replies so far. Battery was brand new a month ago and was starting the car perfectly the day before. In fact it starts instantly now, just stalls straight away.

I have locked and unlocked the car several times, with two different fobs. In fact we never lock the car at night, so there was no change there between it running fine, and not running at all.

I have also tried two code readers - my cheapo reports no codes and a pro grade snapon reader wont communicate with the ECU, which does not feel good.

Sounds like an immobiliser/clocks fault. The snap on not talking to it might be a sign it's immobilised..... but, just for a quick check, take the breather out of the top of the fuel filter and have a look to see if there's fuel in the filter housing, just in case it's a faulty lift pump.

You can get test rings that go around the key and flash when the key is being read, they're a bit cheap and nasty and far from perfect, but they can give you a clue as to whether the immobiliser isn't reading the key

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30 minutes ago, whitelion58 said:

I have also tried two code readers - my cheapo reports no codes and a pro grade snapon reader wont communicate with the ECU, which does not feel good.

Does your OBD reader get power (lights up) but just says "Link Error," or does it stay completely dark when you plug it in?

Try disconnecting battery and leaving for a while then reconnect and see if it makes a difference. When my old Seat imobilser stuck on I gave up on it and left it as I wasnt using car. Battery was flat by the time I got around to looking at it again and once fully charged car was back to normal. When it did happen the AA guy couldnt access the ecu either with his code reader.

Alasdair

5 minutes ago, Stonekeeper said:

Does your OBD reader get power (lights up) but just says "Link Error," or does it stay completely dark when you plug it in?

My cheap reader connects to my app, but reports no codes. The SnapOn beeps and powers up when connected, but fails to read vin data off the ECU and wont fo any further

49 minutes ago, whitelion58 said:

My cheap reader connects to my app, but reports no codes. The SnapOn beeps and powers up when connected, but fails to read vin data off the ECU and wont fo any further

From AI

Also check fuses for ABS

It would be an idea to see if the car starts and runs with the ABS module disconnected too

Edited 23 January23 Jan by Stonekeeper

Thanks again. Disconnected the battery overnight, still the same this morning. Had a look at the fuses and Relay 100 and all look good. Unfortunately the ABS module is buried down behind and underneath the battery box so cannot be reached without a fair degree of spanner work.

I am very inclined to think that this is an immobiliser problem, though accept maybe the ABS module could be it. In either case I suspect repair costs and effort will exceed the value of the car, which is probably around a grand now.

I think we will be looking for a slightly less old replacement, maybe a Superb DSG Estate.

Don't suppose anyone here wants to make an offer on the Octavia and take it away?

Try banging around the ignition switch and raising/lowering steering wheel if it has that option. It may be a bad connection at the chip reader coil. If that doesnt work you could try removing fuses for ABS system. Think they are in fuse box near battery and are strip fuses. They have a tendency to crack but often not noticeable until you remove them . I got my old Seat imobilser deleted as it would stick on randomly although I doubt anyone would bother stealing it.

Alasdair

I had this same issue which turned out to be the immobiliser. Involved a vehicle that had no keys and needed new ones cut. Battery was knackered but it started and ran fine with a jump pack. As soon as we changed the battery, the immobiliser kicked in. Ended up getting the ECU sent away and the immobiliser deleted. Problem solved :) Shouldn't be more than £100 ish to fix it.