Mazda CX-30 - Battery problems

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Thu 4 Jan 2024 13:10
Mazda CX-30 - Battery problems - davecooper

I have a CX-30 Skyactive X which I bought in 2020. I am now looking for a replacement and one option is a nearly new CX-30 as I like the car very much. However, almost from new it has been exhibiting battery problems, specifically after cleaning it. Five or ten minutes with doors or tailgate open and it would not start again. This was not a case of the battery struggling to turn the engine, it was just totally dead. I could have driven a few hundred miles the day before and this would still happen. Initially I had to get recovery round to start it after which he spent half an hour resetting a full house of error codes. I now have a booster to get it started but have to drive the car a few times before I lose the engine malfunction warning message on the dash. I have mentioned this to the dealer but they have only just taken on the Mazda franchise so could not really help but did say that there was a potential problem when leaving doors open for too long!

Anyway, I was doing some digging online and I came across a CX-30 forum which seems to be an American site. However, the battery problem is plastered all over the site and they have been generating a table of owners battery issues so that they can try to get some resolution. Specifically, this problem seems to revolve around having doors open when cleaning the car. If I wash mine without unlocking it, it is fine. Further reading seems to suggest that there is a software update that cures this problem but has not been the subject of a recall as it is not classed as a safety issue.

The bottom line is, before I consider buying another one, I want to know that this problem has gone away. Does anyone know anything about this issue and whether it has been resolved?

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Thu 4 Jan 2024 13:55
Mazda CX-30 - Battery problems - elekie&a/c doctor
From your description of the problem, it’s highly likely the battery is/was below par . Leaving interior lights on for 20 minutes shouldn’t kill a battery on any car . Perhaps the battery on the car when you bought it originally was not the correct type ?
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Thu 4 Jan 2024 14:19
Mazda CX-30 - Battery problems - RT

Some Japanese cars are fitted with small warm weather batteries, quite unsuited to the UK climate - the original battery in my Subaru Outback was a small Panasonic and failed during it's second UK winter - I replaced it with the biggest Bosch that would fit the battery tray and all was fine.

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Thu 4 Jan 2024 18:49
Mazda CX-30 - Battery problems - Engineer Andy

Some Japanese cars are fitted with small warm weather batteries, quite unsuited to the UK climate - the original battery in my Subaru Outback was a small Panasonic and failed during it's second UK winter - I replaced it with the biggest Bosch that would fit the battery tray and all was fine.

In my view, the OEM batteries fitted (I've had three Mazda ones in 18 years, plus my current one is also a Bosch and higher output, fitted this time by the RAC at the end of the first lockdown in 2020) to my Mazda 3, and none of the OEMs have lasted more than 4-5 years.

The current Bosch one (now 3.5 years old) was first 'tested' 5 months after it was fitted, and that time and at every subsequent service around this time the dealer says the 'state of health' has been poor and recommended it be replaced.

Oddly enough, the Bosch battery (which is I think 650CCA as opposed to the OEMs' at 450 or 550) has never missed a beat starting up in all weathers, even in really cold winter weather and when not used for a fortnight. The OEMs always struggled after a year or two in that sort of conditions.

Makes me think about the ethics of my dealership and/or engineering prowess of Mazda sometimes, especially in the light my car's (expensive) current issues with one of its exhaust sensors.

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Thu 4 Jan 2024 14:23
Mazda CX-30 - Battery problems - davecooper

The car was bought new so should have had the correct battery fitted. Have had the battery tested twice and both times came back as healthy. All interior lights are LED as well so should be very little drain on battery. Opening an shutting the powered tailgate two or three times without the engine running has never caused any battery problems at all.

The car wasn't driven for over a week during the snow last year and sat covered in snow in sub zero temperatures. However, it started without any problems at all after that. However, I gave it a brief wash shortly after and actually made an effort to keep the doors open as briefly as possible. Tried to start it afterwards but absolutely dead, not even enough to light any dashboard lights. Started it on the booster but even then it struggled. Engine had then gone into "limp" mode and it took a very cautious drive of around 10 miles before the limp mode cleared and it drove normally. Then took another couple of days before all warning messages cleared.

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Thu 4 Jan 2024 17:12
Mazda CX-30 - Battery problems - bathtub tom

Is it a hybrid? This sounds like a standard problem with the small 12V battery fitted.

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Thu 4 Jan 2024 17:51
Mazda CX-30 - Battery problems - davecooper

Yes, mild hybrid. To be honest, I always thought that the battery in these has a lot of work to do. The Skyactive X engine has a fairly high compression ratio compared to most modern petrol engined cars so it has that to turn that over before anything else.

The car suffered fairly serious damage from a rear offside collision when it was only 6 months old and was a borderline write off. My wife is convinced that this caused the problem. While I am inclined to think not, I can't be 100% sure.

I will probably never know as the car will probably be on a dealers forecourt within the next few months. A great car, just a shame it has caused me a few problems along the way.

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Thu 4 Jan 2024 22:46
Mazda CX-30 - Battery problems - bathtub tom

I'm not well up on all hybrids, but I know Toyotas have a particular problem with the small battery capacity, and as from my daughter's experience, do KIAs.

Toyotas have a 'ready' mode that allows the 12V battery to be charged from the traction battery and starts the engine when necessary to keep everything topped up. I presume others have a similar system.

As my old IT colleagues used to say, have you RTFM?

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Sat 6 Jan 2024 18:01
Mazda CX-30 - Battery problems - Galad

I have a Mazda 2 mild hybrid bought new in 2020. At 11 months old the original stop-start battery died in my workplace car park and was towed to the dealer who left it on charge overnight. Not satisfied that the voltage was what it should be after charging the dealer asked Mazda to have a new battery fitted. I got fobbed off with ‘it’s a one-off thing’. I’ve had 10 new cars over the past 45 years of driving and I’ve never had to replace a battery on my cars some of which have been 15 years old never mind one that’s 11 months old.

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Mon 15 Apr 2024 22:53
Mazda CX-30 - Battery problems - scarlett pimpernel
I had those same issues on a 2020 Mazda 3 Skyactiv X.
It’s a well known issue on the 3 and there is even a technical service bulletin about the issue.
On my car I had a Body control module software update,which partially cured the issue but I also think that the battery was weak and I had it replaced.
The guy from Mazda assist said that battery issues was the main and o my reason for Mazda breakdowns.
I now have a 2022 3 and that’s been fine.
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