12 volt battery replacement query

Steptoe

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The 'resting' voltage on my battery is now down to 12.1V so, coupled with the low battery message when the accessories phase is on for more than a few minutes, I feel it is time for a new one (car is 4 years old with original battery)

The easy option would have been to pop down to Halfords but I've been changing my own batteries for over 50 years so looked on a well-known selling site instead.

What I've found puzzling is that if I searched using the car's reg. no. I was invariably directed to AGM batteries with stop-start capability rather than the cheap and cheerful lead/acid equivalent which I am certain has been fitted to my car by SAIC.

Either it is upselling or perhaps the facelift model does have the AGM type fitted as standard and the sellers are not differencing between the two models?

Can anyone who has fitted a new battery confirm that it is generic code 027? As I will be buying online it will be difficult to return it if it doesn't fit ( I measured the original battery length as 230mm and the quoted 'correct' replacements are 242mm long)

Many thanks
 
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I've seen other threads about changing the 12V battery and recommendations. Try using the search function for "12 volt battery". I'm sure you'll find them. :)
 
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I've seen other threads about changing the 12v battery and recommendations. Try using the search function for "12 volt battery". I'm sure you'll find them. :)
Thanks for your reply but I had already searched the ZS forum using that phrase and found 3 pages of threads. I didn't read every post but most threads related to disconnecting the negative to reset the hardware and carrying a jump starter in case of low battery issues. There is a similar query on the MG5 forum to which a reply suggested that the generic code could be 075 but I've no idea if the OE battery for the MG5 is the same size as for the ZS
 
Hi, I bought a Bosch S5A05 a couple of weeks ago for my 2003 ZS facelift. Fits perfectly and working well, although I haven't really noticed an improvement in the standing voltage (i.e. HV battery not running) from this and the factory fitted SIAC one.

Hope this helps!
 
Hi, I bought a Bosch S5A05 a couple of weeks ago for my 2003 ZS facelift. Fits perfectly and working well, although I haven't really noticed an improvement in the standing voltage (i.e. HV battery not running) from this and the factory fitted SIAC one.

Hope this helps!
Many thanks, yes extremely helpful.

I looked up the specification for the Bosch battery and it's code is 027 and more importantly the length is 242mm so, on the reasonable assumption that the facelifting didn't include the battery tray, I will order a lead/acid equivalent.
 
Many thanks, yes extremely helpful.

I looked up the specification for the Bosch battery and it's code is 027 and more importantly the length is 242mm so, on the reasonable assumption that the facelifting didn't include the battery tray, I will order a lead/acid equivalent.
Ah great. Yes not sure about the tray. I did have to slide it under a lip at the back with a little bit of force, not much. Other than that it’s was a perfect fit.
Let us know how you get on.
 
@Steptoe have you tried looking for Tanya battery service’s ( on-line ).

They offer free next day delivery and are nationwide.
They are used widely by the trade and public.
The Bosch units usually come with a 5 year warranty ( which is handy ) and I think the Excide units are either 4 or 5 years also.
Standing voltage of 12.1 volts is not unusual when using the auxiliary position for running the radio etc, but of course the 12 volt battery is not receiving any charge in this position.
If I am waiting to pick up the grand kids from school, I just leave the car in READY mode anyway TBH.
I always carry a battery booster jumper pack under the drivers seat 💺 anyway 👍.
 
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@Steptoe have you tried looking for Tanya battery service’s ( on-line ).

They offer free next day delivery and are nationwide.
They are used widely by the trade and public.
The Bosch units usually come with a 5 year warranty ( which is handy ) and I think the Excide units are either 4 or 5 years also.
Standing voltage of 12.1 volts is not unusual when using the auxiliary position for running the radio etc, but of course the 12 volt battery is not receiving any charge in this position.
If I am waiting to pick up the grand kids from school, I just leave the car in READY mode anyway TBH.
I always carry a battery booster jumper pack under the drivers seat 💺 anyway 👍.
Hi, yes, when looking online I've been drawn to the Tanya deals so will probably buy from them. I also have a booster pack under the seat but as I measured the 12.1V after the car had been not used for a couple of days it's probably time to change (wistfully remembering a battery in an old Volvo which lasted for about 12 years of daily use!)
 
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To close this thread off I can confirm that a code 027 battery is the correct size for the pre-facelift ZS.

The replacement was timely as a couple of days after posting this query, whenever I opened the door, I got a bong and a a 'red-letter' message instructing me to put the car into 'ready mode' due to low 12V battery.

Thanks again to those who responded.
 
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