[Closed] car battery question

There may be some current drain due to alarm/immobiliser, clock etc. Wouldn't surprise me if it was low.

er.... no with the battery connected to the car it will go flat, certainly on a modern car... be careful jump starting the car too it would be worth taking it off and charging it with a battery charger slowly to avoid damage to the cells.

Ok thanks chaps

As above, all modern cars will drain a battery over time, certain circuits don't turn off. It is usually only a small drain, about a tenth of an amp, but over time that will cause your battery to go flat. Most csrs won't start if left for more than a month so you had little chance sfter 3.
Be careful jump starting the car, as mentioned above it is essy to spike the electrics. Ensure the keys are nowhere near the ignition when you connect up the jump leads. Run the other car for at least 10 minutes before you try to start yours. If in doubt call the AA. We have anti-spike circuits in our boost packs to prevent damage.
If you know the car will be left for a long time it is worth disconnecting the negative battery lead- this will stop your battery going flat.

loddrik - Member

Put a new battery in my car about 4 months ago. Car has been idle for the last three months. Just been to try and start it and the battery is dead. Is this normal? I'd have thought a new battery would have started first time even after 3 months of non use..

Yes, very normal. New battery etc ...

If you are not driving it for 3 months the battery will die (not charging) so need recharging.

Similar situation happens to me all the time and I am now the expert in jump starting car in all sort of ways, even without your radio code.

bikemike1968 - Member
If you know the car will be left for a long time it is worth disconnecting the negative battery lead- this will stop your battery going flat.

Would prefer to do this but I don't have the code for the bloody radio when I bought the car so I need some sort of power to maintain the radio code. I was told I was given the code but I have not. Damn!

Out of interest, how long roughly will a battery last while listening to the radio etc. I was parked up in the peaks recently, watching the sunset and listening to the radio, got a bit paranoid about draining the battery and getting stranded.

jambourgie - Member

Out of interest, how long roughly will a battery last while listening to the radio etc. I was parked up in the peaks recently, watching the sunset and listening to the radio, got a bit paranoid about draining the battery and getting stranded.

Not sure but I doubt you can drain the battery dry in one night or few hours.

🙂

It depends, if you have to turn the ignition on to get the radio on then as little as half an hour. If the radio can be turned without the keys in the ignition then a lot longer- radios don't use much current, all the other circuits on the car do.
Some cars are worse than others- the Honda Jazz is particularly prone to this due to its tiny battery- which is ironic really, as it THE favourite car for sitting in laybys, listening to radio 4 and drinking tea out of tartan vacuum flasks.

Battery codes can often be sourced on eBay/forums for a few quid.

Battery code?

spooky_b329 - Member

Battery codes can often be sourced on eBay/forums for a few quid.

Not the battery code but the standard in car radio code. 🙄

If it's factory-fit, the dealer may be able to look it up.

In addition to the alarm and whatnot, the battery will discharge on its own too. Particularly if it's cold.

Cars with alarms have a button you can press to disable the alarm if you know you're going to be away for a while.

Cougar - Moderator

If it's factory-fit, the dealer may be able to look it up.

Yes, I shall need to do this soon but I bet I will be charged ... 😕