I'm looking for some advice - the dash message (change the key battery!) appeared yesterday.

 

I've changed the battery in the key, but the message still appears when I unlock the car and get in? 

 

 

 

This has been covered several times before.

Make sure that you use a premium brand of battery, with a long date,  and change the battery in your spare key also. Worked for me and other forumeers.

Thanks @gregoir.

 

I'll check the date on the batteries - they are Duracell.

The mk2 key fobs were almost identical but the batteries lasted years in them

The mk3 fob battery need replacing about every 18 months before the warning appears but I don't respond well to nagging and tend to ignore the warnings and they operate normally for a couple of months before I cave in to both the car and the wife's reminders.

If you test the old batteries when they come out they are usually only just below the 1.5v nominal value so do a voltage test on new ones to make sure they are well over the nominal value and also avoid leaving greasy fingermarks on the batteries.

Edited 26 August, 20196 yr by Gerrycan

Thanks @Gerrycan. The bizarre thing is the warning is no longer appearing. My car must be slow on the uptake of battery change!

My key continued working for at least 11 months after the warning appeared. The car was then serviced at a main dealer and the warning has gone away, although they haven't recorded or charged me for changing the battery. However the car is only used once or twice a week on average, so a key in daily use might not last so long after the warning appears.

Having discussed this with my brother, he mentioned his wife had had to change the battery twice on her Fabia within the first 18 months of ownership (from new). 

 

I came from Fords before Skoda, and only ever had to change key fob batteries on average of every 2-3 years. 

 

It's not a serious gripe, more of a middle-aged rant 😂

I forgot to add that the battery warning came on after about three years of light usage. I don't remember changing the key battery on my 16 year old Focus, but I guess I must have at some point.

On 25/08/2019 at 00:57, Wangarai said:

I'm looking for some advice - the dash message (change the key battery!) appeared yesterday.

 

I've changed the battery in the key, but the message still appears when I unlock the car and get in? 

 

The first time after you change the key you will have the same message (if you have Kessy is wont work & you will have to open the doors with the buttons).

After you use the key with the new battery for the first time, the message should dissapear from the next time you leave you car & lock it.

Thanks @Gabbo, that makes sense! 

I got caught out yesterday, when my wife had to walk back from the local supermarket,  having been unable to open the car with the keyfob. ( I had once shown her how to open the door with the key itself , but it was a long time ago and she had forgotten). I walked back with her and the spare key, only to find the same problem. Initially I suspected an issue with the central locking system as, when I got home, I tested the fob batteries and found them both in excess of 3 volts. I changed both batteries about three months ago, but ever since had been getting the low battery warning regularly. I assumed that there was an error in the software or warning system and, foolishly, was happy to ignore those warnings. Before investigating further, and still assuming that the fault lay with the car rather than the key, I changed both batteries for brand new and reputable 2032s rather than the 2025s again. Much to my relief and surprise, all was now well. I presume that, although I appeared to have a good voltage in the older batteries, it was not enough under load to unlock the car. The giveaway, I realised, was that I was getting no LED flash back from the key when I pressed any of the buttons. You learn something every day. My original batteries were on a card bought from a cheapo shop; they work other inconsequential stuff around the house but are clearly not man enough for the keyfob. I suppose the moral is not to keep ignoring a low key battery warning.....

I believe (but I am not 100% sure) that the difference between a 2025 and 2032 is the battery thickness (and capacity). If you fit a 2025 in a hole intended for a 2032 it may not make proper contact. Also it has less capacity.

2032 means 20mm dia and 3.2mm thick. 

Edited 29 July, 20214 yr by TDIum

General rule is thus: replace your CR2025's every year for trouble-free motoring.  Replace them every 6-8 months if you have KESSY (because you get even less warning there and without a working KESSY system, your car won't even start!!!! )

I won't be having KESSY again IF I have another Skoda. It's great when it works, but it has locked me out twice in a month and has got me so paranoid about being locked out that I'm carrying a spare key and at least 4 spare batteries!

 

When it plays up it's too much of a pain in the backside. 

When key battery needs replacing use a CR2032 (higher capacity, will last longer) which will fit even though it's 0.7mm thicker.

An interesting trick, IF you are having low battery issues, hold the key fob against your head when you press the button. The skull cavity acts and an amplifier for the signal (With t being a parabolic chamber its has a positive gain) and you should be able to enter the car.

9 minutes ago, PetrolDave said:

When key battery needs replacing use a CR2032 (higher capacity, will last longer) which will fit even though it's 0.7mm thicker.

I thought about this, but I couldn't see it fitting without on hell of a squeeze getting it in there, so I bottled it and stuck with the 2025.

 

I did have similar difficulty initially but realised that I could insert a slim blade between cover and fob to ease the battery into its housing whilst clicking the cover shut.

3 hours ago, Pagan-Image said:

An interesting trick, IF you are having low battery issues, hold the key fob against your head when you press the button. The skull cavity acts and an amplifier for the signal (With t being a parabolic chamber its has a positive gain) and you should be able to enter the car.

 

Interesting tip there. Should I remove my tin-foil hat before or after entering the car? 

I've encountered a similar issue on a different manufacturer's forum. Advice from the manufacturer is to only use Panasonic batteries. Don't know if it will make a difference, but no harm trying.

32 minutes ago, TDIum said:

 

Interesting tip there. Should I remove my tin-foil hat before or after entering the car? 

Id would remove the hat, it would act as a faraday cage and you could end up opening the fridge by mistake  

My dealer told me that CR2032 presses the chip inside the key too much and causes issues on some users, that’s why I returned back the OEM size CR2025. I have no Kessy, so it should last 2-3 years at least. My original battery lasted 4 years.

On 29/07/2021 at 19:40, TheWanderer said:

I won't be having KESSY again IF I have another Skoda. It's great when it works, but it has locked me out twice in a month and has got me so paranoid about being locked out that I'm carrying a spare key and at least 4 spare batteries!

 

When it plays up it's too much of a pain in the backside. 

I specifically wanted a car without KESSY, but for security reasons.

Have to admit, having a "Start" button would be cool, though.

On 30/07/2021 at 12:44, Routemaster1461 said:

I've encountered a similar issue on a different manufacturer's forum. Advice from the manufacturer is to only use Panasonic batteries. Don't know if it will make a difference, but no harm trying.

 

Yes, well I've only ever fitted Panasonic and the originals were always Panasonic across the VW Group marques, well Audi, VW , SEAT and as is said here Skoda.

Previous cars, both used well, a 2000 VW Passat 4Motion and a 2002 VW Polo 1.4 16V, both got their fob batteries replaced at maybe the 8 year point in their life - why, well just because I thought it was time to do that. Current cars a 2011 Audi S4 very little used and a 2015 VW Polo 1.2TSI got their fob batteries replaced end of last year/ earlier this year, the 2032 in the 2011 S4 were still in good state, the 2025 in the 2015 Polo a lot less so, maybe 3.04V down from the 3.25V of the new Panasonic batteries. Typically when you buy them online, there will be a picture of the actual batteries or a picture from the same card/batch and so the "use by" date can easily be seen, in that case the date was 2029, so that suited me.

Changed my batteries to Duracell and so far so good. Had some Panasonic one's and it seems that they're not as good. 

 

But also it seems that it's not a good idea to put the key on a keyring with other keys as it seems to drain the battery quickly. Still wouldn't have it again.