Octavia TSI DSG (66 plate) Battery Problem

[Samstan]

I’ve had my Octavia hatchback for about 5 months now and love it but I’ve an issue that’s concerning me. Just after it was out of warranty I got a battery needs charging warning. I’d not driven more than about 4 miles in 2 weeks because of lockdown but took it out for about 20 miles and no warning when I started the engine again. Following day warning is back. Again took it out and again fixed it. Left the car a few days and battery totally flat. Given car is 4 years old but had less than 25k on the clock I thought maybe it’s done lots of little trips so the battery was dead. Jump started car and took it to get the battery changed.  Job done I thought.

 

Fast forward 2 weeks and I’d not used the car for 4 days and got battery warning again 😡

 

So battery is definitely charging when I drive as message goes away for a few days but something must be draining the battery. I had something similar in my van and it turned out to be a tracker fitted previously (ex company vehicle).

 

I’m not at all technical so if voltages etc need checking then I’m going to have to pay the garage and having forked out for a new battery plus Xmas fad approaching I’d prefer this to be the last resort.

 

Are there any settings I need to check to make sure stuff isn’t turned on or is there anything that I’m not aware of that could be draining it?

 

Any help gratefully received!

[J.R.]

The alarm siren internal battery failed & leaked acid over the circuit board, remove fuse and see if problem goes away.

 

Have any electrical accessories been fitted recently? Dash cams, different stereo, trailer socket wiring etc?

[Samstan]

Alarm works so would assume that’s ok (accidentally locked the car when I nipped into the shop with husband and dog in there - oops!). Dash cam is plugged into 12v socket and have unplugged that tonight. I have had a tow bar fitted but can’t remember if that was before or after the error message started.

[ords]

You say you've unplugged the dash cam tonight. Does that mean you usually leave it plugged in?  12v socket is live all the time.

[Ecomatt]

If you arent using the car as much as you used to. I would buy a smart plug in solar charger to help keep it topped up. 

[Samstan]

7 hours ago, ords said:

You say you've unplugged the dash cam tonight. Does that mean you usually leave it plugged in?  12v socket is live all the time.

Yes it was - I’d forgotten about until I was sat in the looking through the manual to see if I’d missed anything. Would a dashcam that’s in almost stand by mode (ie screen off and not filming unless the car is knocked) draw enough power to flatten a car battery in a week though? 
 

Ecomatt, I’m still using the car for shopping or now we’re out of lockdown (I’m in Wales) for occasional longer trips to take the dogs to the beach so shouldn’t be necessary for a modern car. That’s why I’m thinking there’s something wrong somewhere (beginning to think it may be the tow bar from the comment above)

[nidza]

What I have learned, during this pandemic lockdowns we had last spring, and the car was standing still for a weeks, this AGM battery needs days of long trips, not hours or minutes, to get back into its original shape. I drive 39kms in one direction to the work and back, so it activated start-stop after such a message only after 3 days of going to work. There is some logic behind smart charging of AGM and optimizing its health, or whatever, and this conditioning obviously needs time and correct temperatures (it was actually very warm during this issue, and too warm or too cold weather, prolongs its conditioning and charging cycles).

 

What also I have learned, if the car doesn't want to start, leave it for 1-2 hours, and then it will start like no issue was there whatsoever, but then you have to drive it. If it is complicated for proper jump start from another car, it is better to go for lunch and come back.

Edited 1 December, 2020 by nidza

[Samstan]

Thanks nidza, that makes sense I guess. It’s the first car I’ve had with stop start and am doing mainly local miles. I assumed same as my van there’s be no issue with the battery unless the vehicle was stood for 2-3 weeks without moving.

[langers2k]

If you have a multimeter, you can measure the standby current of the dashcam to get an idea of how much juice it uses. A quick google suggests that at least some dashcams consume almost as much power in parking mode as they do in normal recording mode!

 

There is a document about finding parasitic current draw, that suggested that a non-modified car should be under 40mA after it's been locked and undisturbed for 2 hours. It's a few years old but that would work out as a maximum of around 0.5W. Looking around, dashcams in parking mode can use anything between 1 and 4W which is why dashcam users often have a fault code about quiescent current being too high.

 

It might be worth investing in a battery saver or separate battery for the dashcam to avoid these problems

[PetrolDave]

10 hours ago, Ecomatt said:

If you aren't using the car as much as you used to. I would buy a smart plug in solar charger to help keep it topped up. 

What I've been doing since the start of Lockdown 1 in March.

[Samstan]

Lingers, thanks but I’m no where near that technical! Checking the oil and in an emergency changing a wheel is about my limit! I’ve unplugged the cam and will just plug it in when I’m going anywhere.

[varaderoguy]

In the intervening time, you might want to invest in a decent battery charger.  As it is getting colder, the battery will be less resilent if it has a lower charge and you could damage the internals of the battery if it only has a low charge (and it will refuse to accept a charge again).

 

Something like this: https://www.ebay.co.uk/itm/Smart-Automatic-Battery-Charger-for-VW-Golf-Inteligent-5-Stage-/172958223584

will recover the battery and keep it on trickle charge whilst you are not using the car.

[Samstan]

I already have one for the van so can charge if needed. Difficult for me to trickle charge as no garage out side plug socket but can charge if needed. 
 

if it’s just a case of I need to drive it further and longer I can do that. I was concerned something was wrong and draining it.

 

thanks all for the help and suggestions 🙂