Mazda CX-3 Forums

My 2015 Q85 battery is the one fitted to the car originally. Due to this virus running around I have been forced to 'shield' for the past few weeks so unfortunately haven't used the car as much as I usually would. As the battery is heading towards five year old I am considering renewing it before it does let me down..
As I see it I have four options, 1. Mazda dealer, 2, Battery specialist, 3. Someone like Halfords etc or 4. Do it myself as I have done on previous cars although they didn't have as much technical stuff like I-stop and cruise control.
I know that the replacement must be like for like or an AGM battery (not lead/acid normal type) , it's more a case of what problems will occur if I change it. I have searched the internet looking for information to do it myself but all I find are key fob or changing normal batteries.

So has anyone here changed their own battery and did they experience any problems? If so what? How did you overcome them? Does anyone know of service sheet that covers battery replacement on I-stop cars?

I love the car but find it frustrating that, as yet, there does not seem to be a Workshop Manual (Haynes etc) available and I'm left searching around the internet for details of how to do things on the car.

Many thanks.

Mine died a couple of weeks ago. Bought an identical Yuasa battery from Country batteries for £130. Easy replacement but was not aware of any special procedures for I stop, which hasn’t cut in since, not that I would expect it to as it rarely did.
Always disconnect negative wire 1st and connect last.

You only need an EFB (Enhanced Flooded Battery) which is one step up from a standard wet battery, type N-55 or Q-85 Start/Stop, no need to go to the extra expense of AGM (Absorbent Glass Mat) type unless you want to.

I've not needed to replace mine yet. The Owner's Manual however, does mention removing the battery if it needs recharging and makes no note about any special procedures when it comes to reinstalling (other than the usual battery handling and connection precautions).

That said, i-stop may not work straight away after you replace the battery; I think sometimes it can take a few days of driving before it's happy, but if it still doesn't work you may need to take the car to a dealer for them to hook it up to their diagnostics computer for i-stop reset. (See attached workshop document, which may be of interest).

Julian
Thank you for that information.
John

I had issues with i-stop and heads-up display playing up – which I then gathered was the battery lying idle in the lockdown.

I bought a small solar panel charger which I fitted (cable ties) to the rear parcel shelf and then wired it into a 12v plug and socket in the boot..

One has to remember to unplug said when driving as the reverse charge can damage the panel..

So far so good – cost £25 ish time about 2 hours.. including fitting 12v socket into boot side panel.

Yesterday, my istop engaged within 100m of leaving home even though the blue engine light was on.

Witfit, I'm surprised that a small solar panel is producing enough amps to make a significant difference to the charge level of your battery, but if it's working for you, that's great. If you connect a diode into the wire to the panel it will eliminate any reverse current flow and negate the need to keep unplugging it.

jtonline wrote: ↑Sun Jun 14, 2020 11:47 pm Witfit, I'm surprised that a small solar panel is producing enough amps to make a significant difference to the charge level of your battery, but if it's working for you, that's great. If you connect a diode into the wire to the panel it will eliminate any reverse current flow and negate the need to keep unplugging it.

Thanks for that - I will do - but in the meantime it has made me install a live 12v socket in the boot which I had been meaning to do..

I have been in contact with the manufacturers of the panel and although there is no mention of a blocking diode - they confirmed one is fitted - so yes I can now leave it connected and I have a 12v live socket in the back. Jtonline you are right that it does not charge but keeps the battery topped up and since it has been set up I have had no blips with the other electronics in the car - one of the reasons is I have a dashcam that requires to be powered when the ignition is off and this does effect the battery performance.. One of the things that concerned me was that it would be affected by the tinted out windows - this is not an issue for solar panels - only to us from a sight view..

To those on here who have used a CteK charger. Do you disconnect the battery from the car electrics or leave it connected as if in normal use. Looking at Ctek information they do not make this totally clear. On my motorcycle the charger is connected to the battery which is still connected to the bikes electrics.