Author Topic: Charging battery overnight (Read 1315 times)

obtom · « **on:** April 23, 2024, 10:47:41 PM »

Hi All,

I’ve got a 3.5 year old Yuasa battery in my mk 2 jazz and for the first time since I put it in I had trouble starting the car (took like 20 seconds of cranking to get going).

If I took the battery out overnight to charge it will I run into problems with the immobiliser? I’ve got the code for the radio so that doesn’t bother me but I’ve got a couple of important trips coming up so don’t want to risk either a flat battery or an obstinate immobiliser!

We gave the car a 40 minute run 2 days ago, didn’t use it yesterday and the voltage reads 12.41 today which doesn’t seem amazing.

Many thanks!
Tom

olduser1 · « **Reply #1 on:** **Today** at 07:11:16 AM »

Treat yourself to CTEK MXS 5.0 Charger , you'll never look back.
No need to remove the battery.
I only replaced the original Yusa on my wife's Mk 2 Jazz last October when it was 9 yrs of age.

Lord Voltermore · « **Reply #2 on:** **Today** at 07:48:54 AM »

I cant comment on any immobiliser problems if for instance you need to remove the battery to reach a 240v power socket.

What do you mean by taking 20 seconds to start? If battery was able to crank the starter reasonably powerfully for 20 seconds before the car started the problem may lie with the car, not the battery.

The resting voltage of a fully charged battery should be 12.6V . 12.41 Volts suggests its partly charged but might still be healthy. .
If you typically only do short journeys even a 40 minute run may not be enough to fully charge it. With the engine running you should be getting more like 14.4 volts.

I also had an asian made Original equipment battery (not Yuasa) that lasted more than 9 years.

GBH · « **Reply #3 on:** **Today** at 09:11:16 AM »

As Lord V points out, if the battery managed to turn the engine for 20 seconds and it then started, the battery would appear to be O.K.

I had to change my battery a few months after buying my (used) car and there was no problem with changing it over as I had a card with the radio code and the coding in the key does not need any input.

Have previously had battery problems with other cars and bought a simple plug-in voltage meter that goes into the cigarette lighter socket. This is easy to use and can be read from the driver's seat when running. They are cheap and readily available through the usual web-sites and are convenient to use as a quick check (or can be left in place without problem).

obtom · « **Reply #4 on:** **Today** at 10:35:15 AM »

Thank you all who've replied so far - this is such a great forum!

Some interesting points:

* I know you can charge a battery whilst still in the car but it's not practical for me as I don't have off street parking near a power supply. Battery will have to come out overnight! I have a charger from the Aldi that I've never tried but should do the trick. Good to know it's probably just the radio that will need a code

* Couple of people mentioned that a battery that can turn the engine over for that long might be ok so I'm not sure what the issue might have been now. I did move the car just a little bit down the road the day before so a neighbour could remove scaffold, but I'd have thought a battery could handle at least a couple of stop/starts like that

John Ratsey · « **Reply #5 on:** **Today** at 01:35:27 PM »

Quote from: obtom on Today at 10:35:15 AM

I did move the car just a little bit down the road the day before so a neighbour could remove scaffold, but I'd have thought a battery could handle at least a couple of stop/starts like that

That's the likely cause of the starting problem. The mixture for the cold engine would have been rich and there would have been fuel left in the cylinders. IIRC, flooring the accelerator pedal next time you start clears the excess.