Charging a flat battery Forums

Anonymous

As my van battery is flat should it charge up just by connecting the mains hookup or does that only charge the leisure battery. I know this has been asked before, maybe even by me but I cannot remember or find the answer.

Feels a bit odd being in the tech section. Sad

nobby

I doubt the onboard charger is adequate for the job.
Strictly speaking you should disconnect the starter battery then fully charge it before reconnecting, though I never do so with mine and it has never made any difference in 45 years motoring!!.
Because it has gone flat you may already be suffereing from sulphation and the battery is already going down hill.

nobby

Anonymous

Thanks for that Nobby. I think under the circumstances I had better remove the leads off the battery and charge it up properly.

GeorgeTelford

Hi Pusser

First thing to ask regarding the Flat starter battery is there a reason? ie did you leave lights or stereo on? If not the battery could be on the way out and charging will only provide a temporary solution.

Next thing is with all the modern gismo's can you remove the battery wihout needing reset codes etc for the vehicle?

George

Anonymous

Never thought of that George. I suspect as it has a Kenwood radio thingy that I will lose the code if I unbuckle it. I think I will charge it up connected. The battery may be on its way out although it has been idle since early December, maybe even November and the radio is always on even when turn off i.e. the radio says in words ALL OFF but this stays on all the time. This may have trickled the battery down but it would not suprise me if a new battery is required.

Thanks for the advice given in a nick of time re the code.

spykal · Moderator

[quote:bc747c6ea1="Pusser"]The battery may be on its way out although it has been idle since early December, maybe even November and the radio is always on even when turn off i.e. the radio says in words ALL OFF but this stays on all the time. This may have trickled the battery down but it would not suprise me if a new battery is required.
[/quote:bc747c6ea1]

Hi Pusser,

This is how most folks ruin their battery, not by using it, but exactly the opposite Crying or Very sad

, it is most important to keep a lead acid battery fully charged to avoid it degrading, this is not so much of a problem in the summer months when you are out and about in the van but in the winter it is worth connecting a charger to the battery once a fortnight....or get one of the sort that can be connected all the time and maintain the battery automatically.

By the way it sounds as though you may have to replace the battery soon so now is the time to make sure you do have the radio code. If you do not have the code, it is possible to change the battery using another battery with jump leads to the terminals to maintain the radio code while you fix the new battery in place. (but be very carefull not to let the leads touch any metal part of the van while you are doing it).

Mike

GeorgeTelford

Hi Pusser

If its been low for quite a while it will probably be well sulphated, this can be reversed by a good charger, but it probably wont recover fully.

With new commercial batteries costing low £30's, probably worth replacing.

Also it may be worth planning a charging system for next years lay up, even without an actual drain, batteries lose charge by just sitting.

George

GeorgeTelford

Hi re Changing battery and retaining codes, the local Kwik fits have a device for m,aintaining power toretain the codes. You have to be careful with Jump leads it only takes a bit of movement to lose the connection and the codes. Also Mikes point about accidental shorts is very important.

George

Anonymous

Hi all,

On boats (thats where I´m coming from) we use a heavy duty rotory switch that can swich from all off/both on/batt1 on/ batt2 on.

Are these never used on MH?

This way you can use any battery for any function.

I dont like them as I like to have a system that keeps the eng/batt for that funcion only but I do have a set of leads that can be used to start the engine from the domestic battery.

Doug...

nobby

One way to keep the codes is to apply 12 volts to the cig lighter socket but remember that the battery leads will then stay "live" whilst you do whatever.

nobby