Dave R

Im not in a position to charge the battery on the car, so are there any issues with removing the battery to charge it overnight?

Will i loose any settings/codes?

Is there a proceedure for doing this ie. remove pos first and reconnect neg first?

The main reason i want to try this is that the heater blower only works at a full speed on demist or auto but not manual mode and i have read that this could be power preservation for a lowish battery. This kind of makes sense as it has all worked ok during longish trips whereby the battery my be getting more charge?

hooch999

I would rather try to get an decent automatic charger, open the hood and the trunk and charge it in place. Much less headaches.

Curmudgeon

He is not in a position to charge the battery in the vehicle, as stated.
If the electrical system gets this persnickety because of the battery, just get a new battery.
FYI, it is negative off first and on last.

Andy_E61

Yes, normally. The car does not know that you charged the battery already.
Normally not, but maybe.
Sounds like you have a serious problem with either the battery itself or the Intelligent Battery Sensor.
But, just replacing the battery and praying does not help.

JasonH

If you only do short journeys or use the car infrequently then charging the battery is fine, otherwise you should probably replace the battery (given your symptoms).

My advice on the best way to do this is:

1)Get access to the battery - remove the cover etc. leave the boot/tailgate open.
2)Leave the doors etc. alone for 16 mins - the car will go to sleep. You can tell it's asleep because the park indicator next to the gearchange (auto) goes out.
3)Now 10mm ratchet to loosen the battery negative and lift it cleanly off.
4)Wrap a rag round the negative lead to prevent accidental reconnection then disconnect the positive.

Should get no fault codes if you cleanly reconnect the battery.

Note:

a) If you open any door, or the bonnet the 16 min countdown starts again.
b) Without power you can't easily lock the doors and you may not be able to open the boot/tailgate once shut (you can't open my tailgate).
c) The intelligent battery sensor won't know you've charged the battery. This isn't too bad really you just risk the odd erroneous warning like "High rate of battery discharge". The battery will still charge fine and the car will be fine.
d) The battery terminals will lift off easily once undone, don't lever them off or you could destroy the IBS which is built into the battery negative terminal.

So all in a bit of a pain. Much easier if you can get a lead to the charge points under the bonnet. If the leads are thin (trickle charger) you can close the bonnet with the clips on.