- My model of MX-5 is:Mk 3.5 2010
- I’m based near: Haslingden
- I’m looking for technical help or recommendations on: Batteries
Hello all.
I went to start the car this morning but the battery was stone dead, the car started ok with a jump, checked the input at 14.9v. The battery was new in June when I bought the car. I am pretty sure that overnight temps caused the failure. Question, is there a battery type that can with stand colder night time temps?
Thanks for reading and a happy chrimbo
Bob
Hi Bob,
Not answering your question but asking you a question.
When was the last time you started/used the car?
Reason I ask is that the NC is known to drain the battery when not in use. I found on mine that 2 to 3 weeks and it would need a jump start.
Another one that catches out owners is that the boot lid can be popped leaving the lid looking like it’s closed but the boot light is on.
Richard.
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The boot light on my 3.5 operates from a switch in the boot with no auto switch on the boot lid. Make sure the light is switched off. If leaving the car for a couple of weeks it may be wise to connect a battery conditioner that will monitor the battery and keep it topped up. I have done this on my 2.5 and keeps the battery in tip top condition during longer periods of non use.
There’s an auto switch off though when the lid is closed fully.
Couldn’t find a micro switch and the wife refused to be shut in the boot to check the light!
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Hello Richard
A couple of weeks ago. I have solar charger I will connect to the car as soon as. I turned the boot light off.
Ta
The boot light “auto” switch is built into the lock mechanism.
Once the boot lock is released the boot lid has to raise 2 or 3mm and the boot light will come on.
I do the same as you with a battery conditioner. It’s been very useful this year!
Richard.
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Thanks
I will connect a Solar powered charger to it as soon as
Ta
Not much use TBH, even less so with no sun. Get a maintenance charger👍 if you can hook it up to a power source.
Make sure the battery is fully charged, the solar panel will struggle to charge the battery.
Richard.
Any old battery is going to be vulnerable in cold weather, especially if a car gets parked up for weeks on end without use. And MX-5s, which are often owned as second cars, and summer playthings, are likely to suffer more in this respect than daily drives.
So, if you intend to park your 5 without use over the winter, then you must regularly treat your battery to conditioning charges - preferably every week.
If you have a garage, then purchase a smart charger, which can be left connected permanently, and the smart bit of the charger, means that it will charge and then turn off automatically, then turn on again when the battery tells the charger it needs a top up.
Personally, I do not have a garage, but I do have a private, off-road parking space, so I simply connect my battery for a conditioning charge once a week - it takes about three to four hours. This keeps it topped up, and always ready for use.
Mobile phone in the boot, hit record on the video, shut the boot lid light on and watch it go off.
If it doesn’t you have a dodgy switch, happy wife though.
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Exactly what you say happened to mine. It was 9 years old when it decided it didn’t want to play anymore. Probably helped it on it’s way to premature failure by not keeping it maintained during the winter months.
A new battery and a newly purchased maintenance charger for the winter months 3 years ago. I keep switching it on every other day, keeps it ready to go whenever.
If the battery was completely flat even though it’s new it might not fully recharge,it could need replacing don’t just measure voltage measure the CCA, this is what catches lots of people out.
Always worth having a battery tender connected, even more so in the winter.
CTek very good.
Thanks all for the helpful comments. The car started this morning after a very cold night , the inside of the glass was frosted up so I had a fan heater inside to dry things out. I normally don’t have access to 240v so I will be going down the solar route and look for a better quality battery.
Thanks again all