Just wondered whether anyone knows what the original battery specifications are for my Fabia. I can't seem to find them, and the current battery fitted by the previous owner is a rather sad aftermarket job at 40Ahr 360 CCA which isn't holding its charge. My trips are mostly short city drives, with a motorway drive once every two months.

 

I'm reluctant to get a battery with an Ahr capacity that exceeds the OEM battery by too much, as I understand that batteries are originally selected with the current output of the alternator in mind, which in my Fabia's case is 70 Amp (larger engines with larger batteries have higher output alternators). Alternators that have to work too hard may overheat, or so I understand.

If you look at the spec list on a label in the boot there will be a code for the battery - J0N - which relates to Battery 330 A (61 Ah) on my 1.4TDI, but I would just buy what a seller such as Tanya Batteries recommend.

VW Group Option Codes Decoder (igorweb.org)

Edited 15 April, 20233 yr by KeithCheetham

A larger battery does not put a strain on the alternator. The alternator just puts in what other systems take out. The battery is just storage. 

Many thanks to you both -- and also to Pete.

 

It appears my model should have a 60Ah battery, 50% more than the 40Ah than is currently installed, which explains a lot.

 

The 'options' label decoder is very handy too. Thanks for that.

 

T.

3 hours ago, Jocko said:

A larger battery does not put a strain on the alternator. The alternator just puts in what other systems take out. The battery is just storage. 

Putting on my pedantic hat, lead-acid batteries don't actually 'store' energy - they produce energy by a reversible chemical process. Capacitors (or supercapacitors) store energy.   

5 hours ago, Warrior193 said:

Putting on my pedantic hat, lead-acid batteries don't actually 'store' energy - they produce energy by a reversible chemical process. Capacitors (or supercapacitors) store energy.   

I'll grant you that, but it is easier for the layman to consider it as a form of storage rather than Pb and H2SO4 doing magic.