With just ignition on after a minute the yellow battery light comes on if gose off when I start car. The start stop works ok for about 3 to 4 hours then stops working last week it stopped completely so I charged the battery then it worked again for 3 to 4 hours.

Any ideas?

Removed due to early morning brain fade 🙃

Edited 7 October, 20257 Oct by PetrolDave

Sorry - what is the question?

Do you think the battery is not being charged correctly by the vehicles alternator - even though the alternator symbol is extinguishing after the engine is started?

Do you have a meter you can use to measure the battery terminal voltage while the engine is running?

39 minutes ago, PetrolDave said:

If you don't tell the battery management you've fitted a new battery it assumes the old battery is still fitted.

I'm not sure but I think the BMS is SFD locked on the Octavia 4?

OP says battery was charged - not changed.

25 minutes ago, Warrior193 said:

OP says battery was charged - not changed.

My bad, too early in the morning!!!

If start/stop only works for a few hours then that suggests the battery charge state isn't being maintained. How old is the battery?

Edited 7 October, 20257 Oct by PetrolDave

Do you get either of these on the display

Car only 1 yeas old I've had it 3 months

25 minutes ago, Stonekeeper said:

Do you get either of these on the display

No just stops working i drive all day it's fine for about 4 hours

54 minutes ago, Tonyduncan said:

Car only 1 yeas old I've had it 3 months

49 minutes ago, Tonyduncan said:

No just stops working i drive all day it's fine for about 4 hours

You seem to be saying that you think the alternator is not charging the battery correctly - even though the alternator indicator is extinguishing while the engine is running - is that correct??? - If so, as I posted earlier, you need to check the battery terminal voltage while the engine is running.

55 minutes ago, Tonyduncan said:

No just stops working i drive all day it's fine for about 4 hours

Do you not see either when it is working?

3 minutes ago, Warrior193 said:

If so, as I posted earlier, you need to check the battery terminal voltage while the engine is running.

I 100% agree, get the multimeter out and start doing some battery voltage measurements.

25 minutes ago, Stonekeeper said:

Do you not see either when it is working?

No just the A with a line through it

26 minutes ago, PetrolDave said:

I 100% agree, get the multimeter out and start doing some battery voltage measurements.

What should it be at

Running

Idil

4 minutes ago, Tonyduncan said:

What should it be at

Running

Idil

There isn't one answer to that as the car has a Battery Management System that dynamically changes the battery voltage.

Before starting if the voltage is below 12V then that's cause for concern, when the engine is first started expect something around 14V but this will drop to something over 12.5V after a few minutes except when you come off the throttle when it will rise again to around 14V as the "micro regenerative braking" comes into effect.

1 minute ago, Tonyduncan said:

No just the A with a line through it

When the a with the line through it appears it means the stop/start system is operating but has chosen not to stop the engine because the battery is not within the parameters required for the system to function.

There maybe too many other demands on the battery Aircon, cooling fan , headlights, heated seats etc.

Or the battery is below 80% or a combination of all above.

I would doubt the battery or alternator have a fault with the age of the car.

Potentially it is use and the demands of the eu that is stopping it working.

To explain or prove that theory needs a bit of the cars history

What is the mileage now and what was it three months ago at 9-10 month old.

Are your trips often or not and short or long journeys

https://www.varta-automotive.com/knowledge/articles/article-details/start-stop-does-not-work

Edited 7 October, 20257 Oct by Stonekeeper

1 hour ago, Tonyduncan said:

No just the A with a line through it

The messages that @Stonekeeper is referring to are in the vehicle status display (in the infotainment system) - not on the instrument cluster.

1 hour ago, Stonekeeper said:

When the a with the line through it appears it means the stop/start system is operating but has chosen not to stop the engine because the battery is not within the parameters required for the system to function.

There maybe too many other demands on the battery Aircon, cooling fan , headlights, heated seats etc.

Or the battery is below 80% or a combination of all above.

I would doubt the battery or alternator have a fault with the age of the car.

Potentially it is use and the demands of the eu that is stopping it working.

To explain or prove that theory needs a bit of the cars history

What is the mileage now and what was it three months ago at 9-10 month old.

Are your trips often or not and short or long journeys

https://www.varta-automotive.com/knowledge/articles/article-details/start-stop-does-not-work

Possibly not a good assumption to make that a one year old alternator or battery in unlikely to be faulty - My Octavia had both replaced at less than a year because they had failed.

4 minutes ago, Warrior193 said:

Possibly not a good assumption to make that a one year old alternator or battery in unlikely to be faulty - My Octavia had both replaced at less than a year because they had failed.

I agree it's not impossible for a faulty component to have been installed at the factory but I find it best to eliminate other simpler possibilities before taking it to the main dealer for a diagnosis and repair under warranty.

They will initially almost certainly just dismiss with charging the battery back up properly then giving it the customer back.

Especially stop/start because there are so many reasons it deactivates.

If the op had said the crossed out a was not visible it may be different. But that does suggest it's working.

One question i have missed is "When the op charged the battery where did he connect the negative lead of the charger if the battery remained connected in the car?" and "What charger was it and for how long?" sorry that's two questions.

@Tonyduncan could help himself by answering some of the pertinent questions already asked.

Edited 7 October, 20257 Oct by Warrior193
added information

Calling @Tonyduncan please can you answer some of the above questions?

14 minutes ago, Warrior193 said:

Calling @Tonyduncan please can you answer some of the above questions?

Not been online for 3 - 4 hours so possibly driving. I'd wait until the eveing for a reply

6 minutes ago, Lee01 said:

Not been online for 3 - 4 hours so possibly driving. I'd wait until the evening for a reply

Hopefully,

a good 3 hour drive may fix the problem.

6 hours ago, Stonekeeper said:

When the a with the line through it appears it means the stop/start system is operating but has chosen not to stop the engine because the battery is not within the parameters required for the system to function.

There maybe too many other demands on the battery Aircon, cooling fan , headlights, heated seats etc.

Or the battery is below 80% or a combination of all above.

I would doubt the battery or alternator have a fault with the age of the car.

Potentially it is use and the demands of the eu that is stopping it working.

To explain or prove that theory needs a bit of the cars history

What is the mileage now and what was it three months ago at 9-10 month old.

Are your trips often or not and short or long journeys

https://www.varta-automotive.com/knowledge/articles/article-details/start-stop-does-not-work

Car has done 4000 miles in last 3 months short and long journeys 8 hours a day didn't have this problem with my 2015 skoda octavia only once after 7 years and had to change the battery.

Sorry just got home

5 hours ago, Stonekeeper said:

I agree it's not impossible for a faulty component to have been installed at the factory but I find it best to eliminate other simpler possibilities before taking it to the main dealer for a diagnosis and repair under warranty.

They will initially almost certainly just dismiss with charging the battery back up properly then giving it the customer back.

Especially stop/start because there are so many reasons it deactivates.

If the op had said the crossed out a was not visible it may be different. But that does suggest it's working.

One question i have missed is "When the op charged the battery where did he connect the negative lead of the charger if the battery remained connected in the car?" and "What charger was it and for how long?" sorry that's two questions.

Negative leas to engine block

Charged full

Start power was 12.4v

Finished was 13.2v

5 hours ago, Warrior193 said:

The messages that @Stonekeeper is referring to are in the vehicle status display (in the infotainment system) - not on the instrument cluster.

Nothing in the status display