Hi all,

Long time lurker, first time poster here with an ask for help.

I have an issue with Auto Start Stop (ASS), and not because I hate it (though I'm starting to), and not due to an old battery or dodgy starter.

The event

Coming up to a roundabout the ASS kicked in and cut the engine, just as it did that I pressed the disable ASS button.

The car then didn't turn back on when I lifted my foot off the brake and told me to start manually. I tried and it didn't restart. It left me stranded and after calling the AA, and 40 mins later, the car decided to restart (long after disconnecting and reconnecting battery etc). Drove home without a hitch and the AA man decided it was my starter, after it wouldn't restart.

Now, since then and leaving overnight, I've managed to start the car several times, and even took it on a 40 minute drive, where upon coming home and parking I allowed ASS to cut the engine. Same thing happened again, it didn't restart, told me to start manually, and proceeded not to start, until the next day.

Additional context:

• I had a new starter motor fitted in October 25

• At my last service, Jan 26, a new battery was fitted

• Before I drove the car after the event, whenever I'd start and stop the car parked the MFD would say "Move gear selector to P!"

  • this error went away after my 40 min drive

So, I believe it's one of a few options

• Battery hasn't been coded into the car and the car is freaking out (possible but I trust the garage, and I've had it a month since the last service)

• The original battery was an AGM and it was replaced with an EFB and the car isn't happy (again possible, but I would have expected the garage to advise me of the downgrade, we suspect the last battery was the original)

• The ASS event that started this really upset the car and has created a recurring error (I don't have a OBD reader specialised enough to to check the codes, or if this is even possible)

Has anyone had issues with ASS on a mechanically sound car?

Thank you for your help in advance!

Matt

P.S. apologies in advance for an rule breaking, this is my first time on here!

It sounds a lot like conditions are not being "set" for the starter motor to run/engage, and mainly I'd think, that will come down to the DSG selector assembly.

Having an AGM battery from factory is unusual for a small petrol engine, the battery management part of a controller should have been configured to reflect that AGM battery being fitted, it would be useful if you had a suitable scan tool to check what the car thinks is fitted to it now in terms of battery technology and capacity. This will be a separate thing to the failure of the start motor to run - or be asked/enabled to run.

Edit:- again having a suitable scan tool like VCDS would let you check if "starter enabled" was being "set" when you tried to start the car and it refused to activate the starter motor. I would have hoped a proper workshop would have checked this, I can understand why they would whip out the AGM and fit a "correct" battery - but again I'd hope that they would have checked which type and size of battery the car had already been set up for prior to them changing the battery.

Edited 14 February14 Feb by rum4mo

Yes makes sense, I'll be calling them on Monday to see what they think about it.

One thing I forgot to mention was that in the "secret" MFD menu, after turning the car off and holding the "0.0 / SET" button to get to the Battery SOC page, the status says "--%".

Which says to me that the car and battery aren't communicating properly, because clearly there's some charge to start the car in the first place

Edited 14 February14 Feb by kasamasa123

My 2016 1.2 TSI MT5 came with an EFB battery, which is still in the car at 94K miles.

I also wouldn't expect to see an AGM battery in a 2016 Fabia.

Because the battery SOC varies a lot on a car with Stop Start they don't show the SOC % any more.

Have you seen this post : -

Thanks. AG Falco

Thanks I had a look at the post; perhaps this is causing the issue, though what confuses me is this error didn't show after the drive, but the car still failed to restart after ASS event.

The same error did return after my test drive, so perhaps it is this and it just decided to fail

4 hours ago, kasamasa123 said:

Move gear selector to P

ETA: I missed the link that's already been put up, bear in mind these things can be intermittent, at first at least. The systems are vey complex and need all the ducks in a line to operate and to be fair some of it can be about safety or perceived lack of.

Edited 14 February14 Feb by nta16

21 hours ago, kasamasa123 said:

Yes makes sense, I'll be calling them on Monday to see what they think about it.

One thing I forgot to mention was that in the "secret" MFD menu, after turning the car off and holding the "0.0 / SET" button to get to the Battery SOC page, the status says "--%".

Which says to me that the car and battery aren't communicating properly, because clearly there's some charge to start the car in the first place

Your blank battery status display is normal - that function was disabled by Skoda some time before MY16 (Sept/Oct 2015)

If the battery type was actually changed from AGM to EFB, that change should have been registered (adapted) into the vehicles BCM.