Hi guys

wife took the car this afternoon and car started fine. Got out at the shop and come out to it not starting. Wipers went mad and fuel house was zero. 
I checked the battery with the multimeter and it was reading 11.7. I risked jumping it via the van and managed to get it going. 
my question is, should I change the battery as we’ve had the car from new so the battery is 8 years old. Or could the alternator be playing up?

it’s been starting perfectly fine until today for the first time. 
 

oh the start stop hasn’t worked for a couple of years if I remember rightly. 

EIGHT years - you are well into borrowed time!

Why should wipers go mad, etc is my only concern but low volts does some dodgy things...

Check alternator output with your voltmeter.

I'll be the first to say (probably) change it but, personally, I'd spend the time to fully charge it then discharge through a headlamp bulb taking readings of voltage and current every 15 min or so  down to 10.5V (if you can be bothered- I can but I'm a battery saving Geek - where possible and sensible) Then immediately recharge to avoid sulphation if it is any good
I'll probably bet and would love to know if it has low capacity (Ah) and if under 40% definitely change BUT I'm sure others will say just change it and that, of course, is up to you!!!

https://batteryuniversity.com/articles

https://batteryuniversity.com/article/bu-806-tracking-battery-capacity-and-resistance-as-part-of-aging

Thanks for the reply. 
Yes it’s the original battery, I assume that’s what you’re referring to?

when you say change it, do mean the battery or the alternator?

can you advise me on how to check the alternator please?

Shocked that no one else has said just change, the battery just due to age!
At 1500Rev/min with no additional electrical loads, the system voltage should be 14.1-15.1V and perhaps 2.5V above the base voltage with engine off

Make sure to test after removing surface charge immediately after battery charging by turning headlights on for 30s or so then off and measure.

If alternator is charging at those voltage levels (can be max 15.2 if Smart Charging and in a refresh phase) then most likely battery so either test or just change (it has done well and current (pun!) weather conditions are the classic times for failing due to capacity?
The like of Halfords will test battery and alternator if you trust them?

There are other issues such as resetting the charge level for Stop/Start operation but that is another ball game.

3 hours ago, Macka09 said:

should I change the battery as we’ve had the car from new so the battery is 8 years old.

Battery has gone to that big scrapyard in the sky. 🙁

Get it replaced ASAP as an alternator trying to charge a failing battery is under a heavy load and it can lead to damage.

 

 

12 hours ago, Shearers said:

Shocked that no one else has said just change, the battery just due to age!
At 1500Rev/min with no additional electrical loads, the system voltage should be 14.1-15.1V and perhaps 2.5V above the base voltage with engine off

Make sure to test after removing surface charge immediately after battery charging by turning headlights on for 30s or so then off and measure.

If alternator is charging at those voltage levels (can be max 15.2 if Smart Charging and in a refresh phase) then most likely battery so either test or just change (it has done well and current (pun!) weather conditions are the classic times for failing due to capacity?
The like of Halfords will test battery and alternator if you trust them?

There are other issues such as resetting the charge level for Stop/Start operation but that is another ball game.

Thanks for the reply. I managed to jump it and without any thought I just gave it a run for 15 miles and parked it up at home. 
 

What do mean by putting the lights on and checking again?

 

Any recommendations for a replacement battery? What’s the issues after changing the battery?

The lights item was only if you charged the battery and wanted to check the voltage straight after.

I think, from your answers that you should take it to be tested today and be prepared to get a new battery and hopefully the alternator will be checked and found to be OK.

I'd tentatively suggest just going to Halfords as they have good stocks, prices you can compare and a nationwide replacement if it fails. Their own brand 4 year "warranty" against manufacturing defects is IMHO a reasonable compromise rather than the much more expensive Yuasa.

After the battery is changed, the car needs to be told that a new one has been fitted which requires a button pushing procedure that varies by vehicle BUT SHOULD BE INSISTED ON IF A SELLER CHANGES IT FOR YOU.

This is the long answer but you may decide to use @unofix's shorter version!!!