Multiple low voltage warnings on cold days yet starts no issue (car just serviced)

[lukk]

Hi, 

 

My car has displayed multiple low battery voltage warnings over this winter yet it always starts on the first try. I just had it serviced a month ago  - the battery was tested and found to be fine. This is similar to previous years, also warnings on cold days yet no issues and the battery always passed the service check. The car is 7 years old now and according to my knowledge is on its original battery, but then it was 2 years old when I got it.  

 

Is it time to replace the battery? Can I check the voltage of the battery using ODB11 Scanner which I have?

 

Note - I always turn the start stop function off and I live in Ireland where the climate isn't the harshest

[SurreyJohn]

I suspect at 7 years the battery is on the way out, and needs replacing.  Probably better to do this in a controlled way, where you can source a good price than pay lots in a panic when it fails.

 

Is the battery being checked on a cold frosty morning before start up, or after the car has been on a run, engine bay warmed up, and recharged on the way to workshop.  
 

 

 

[lukk]

good question - I usually do in in December so this would speak for it be checked closed to the most extreme conditions it is used. The car usually stays overnight the nigth before just outside the fence surrounding the dealer's place from which they pick it up. So there would be no drive preceding it. I cant comment on whether they keep it inside the garage, where it's warmer than outside, before starting the check.

[lukk]

BTW is this a single battery or two different battery packs - one for start-stop and one to start the car

 

Edited 26 January, 2023 by lukk

[Breezy_Pete]

Single

[varooom]

The warnings come when you're demanding more power than is stored in the battery, and what the alternator can supply.

 

Your battery is original, as it has the QR code label and a VAG part number on it, my battery was the same as yours, Varta and 7 years old when I replaced mine.  I was NOT getting any warnings, but I also knew it was getting tired and best to change before it was kaput.

[lukk]

1 hour ago, SurreyJohn said:

I suspect at 7 years the battery is on the way out, and needs replacing.  Probably better to do this in a controlled way, where you can source a good price than pay lots in a panic when it fails.

 

Is the battery being checked on a cold frosty morning before start up, or after the car has been on a run, engine bay warmed up, and recharged on the way to workshop.  
 

what brand did you replace it with?

 

 

20 minutes ago, varooom said:

The warnings come when you're demanding more power than is stored in the battery, and what the alternator can supply.

 

Your battery is original, as it has the QR code label and a VAG part number on it, my battery was the same as yours, Varta and 7 years old when I replaced mine.  I was NOT getting any warnings, but I also knew it was getting tired and best to change before it was kaput.

 

[varooom]

To be fair to @SurreyJohn that might have been replaced in the last 7 years, but there should be a date stamp probably on your negative terminal, or the plastic cover on negative terminal.  Either way he is spot about getting it changed now rather than later, you might be stranded on side of the road.

[Micky 32]

The electronics can be sensitive on these cars. Also remember they are kept at a charge of 80%. Throw in a few stop starts and it’s not surprising a few errors come up. My Passat has the exact same battery(6 years) and for the last 2/3 years i get some low voltage errors . My car started no problem at -7 degrees couple of weeks back.

 

Unless you have low cranking and/or hard morning starts I wouldn’t be too concerned.

Edited 27 January, 2023 by Micky 32

[Danoid]

I’d be more inclined to change the battery if you use it every day and still got the warnings.

 

I started my car the other day and got the 12 low charge by driving, warning but I expected that as it was very cold and don’t think I used my car for a few weeks.

 

When I saw that messaged I drove a long route and near the destination I enabled stop/start and it worked fine

[varooom]

14 hours ago, lukk said:

My car has displayed multiple low battery voltage warnings over this winter yet it always starts on the first try.

I would assume you have had multiple as you have stated, I would not wait to let it die, as said here by John...

 

14 hours ago, SurreyJohn said:

Probably better to do this in a controlled way, where you can source a good price than pay lots in a panic when it fails.

 

So you have both sides now, to replace or not to replace is now your choice. 🤝

[lukk]

Should I replace my battery with an AGM battery? I see non-AGM ones at 100 euro plus and AGM ones at double the price. Are AGMs dedicated for start stop?

[varooom]

2 minutes ago, lukk said:

Should I replace my battery with an AGM battery? I see non-AGM ones at 100 euro plus and AGM ones at double the price. Are AGMs dedicated for start stop?

AGM's are made for Stop/Start, EFB's are the "weaker" version.

 

Some reading material for you

https://procarmanuals.com/pdf-online-vag-ssp-504-vehicle-batteries/

https://procarmanuals.com/pdf-online-vag-ssp-426-start-stop-system-2009/

[Legacy]

The newer models come with EFB batteries (mine did anyway).  In any event, you'll need to get the battery coded to the car so that the car knows at a minimum that it has a new battery and also the type (AGM/EFM) and capacity.  The alternator is 'smart' and will charge the new battery incorrectly if it thinks that its still charging the older, weaker battery.

 

In terms of coding the battery, anyone with Carista/OBDEleven etc can do that for you.  Otherwise a local mechanic/Halfords might (not sure I'd let Halfords staff near my car if my local branch is anything to go by)

[lukk]

On 27/01/2023 at 10:48, Legacy said:

The newer models come with EFB batteries (mine did anyway).  In any event, you'll need to get the battery coded to the car so that the car knows at a minimum that it has a new battery and also the type (AGM/EFM) and capacity.  The alternator is 'smart' and will charge the new battery incorrectly if it thinks that its still charging the older, weaker battery.

 

In terms of coding the battery, anyone with Carista/OBDEleven etc can do that for you.  Otherwise a local mechanic/Halfords might (not sure I'd let Halfords staff near my car if my local branch is anything to go by)

thanks I have ODB11 and watched a video how to do it. Easy enough. I got AGM from Platinum, will install it and code it tomorrow.