E30 Zone

My Battery keeps going flat after 3 days if I dont use it,are there any common faults with this,battery is on charge now,will check if boot light stays on,otherwise no idea HELP

when you've charged it up take your car and get a battery test done
on it at one of these motorfactor places they do em for free
as it could be either a knackered battery or you've a power drain on it
has it got an alarm fitted? as mine has a clifford one fitted and it drains
mine if it's been parked up for a week

Sorry Jason mate i have no solution but i do know how annoying it is as my battery is doin exactly the same thing except mine goes flat in about 1-2 days at first i thought it was my sub and amp maybe id wired them in wrong and they were draining the battery but its not cos ive taken them out and its still goin flat
hopefully its a common fault that someone knows about and they can put an end to our misery

Fingers crossed

Matt

A common cause of this is the diode pack in the alternator dying.

The easiest way to check is to charge your battery up and fit it to the car, start it up to make sure the battery is really charged.

Switch off the engine, remove the battery negative cable and then just touch it against the negative battery post, there should be a slight spark, if you get a fairly decent spark something is drawing power that shouldn't.

Next, unplug all wires from the alternator and do the 'touch the wire against the battery post' bit again, if it sparks less you have found your culprit.

If you have a multi-meter, use it and see how much current draw is flowing with ignition off etc, make sure all doors are closed etc so no lights are on.. blah blah.

What can happen with alternators is that the diodes (think one-way valve) give up, allowing electricity to flow both ways.

With the engine running, the alternator charges up fine, with power flowing from the alt. to the battery, when the engine is not running, the faulty diode lets power flow back from the battery to the alt. and energises the coils inside it, flattening the battery in the process.

I have seen this problem many times, don't rush out and buy an alt. do the tests first as it could well be a dodgy alarm/stereo/amp/boot light etc.

Worth a go though

Cheers Andy,some good advice there,will check it out later

Here something you might find helpfull. I don't know where you can buy this outside scandinavia...

It is called a Startloop. You just plug it in the cigarett-output and wait for a beep and turn the ignition. After starting the car... leave it in the cigarett-output until it beeps again. Now you got power on it to start the car next time you left your car standing. Picture below (so you know how it looks like).

I forgot to mention that it should not be used on cars with above 2.0l engine. Or diesel engines.

To sort this out you need a milliampmeter and a bit of logical fault finding.
Meter doesn't have to be anything fancy. Just needs to be able to measure up to abot 2A DC.

Kenneth

Where do you get a startloop from?

I am thinking of buying a solar panel to slowly charge in the glorious sun we have here in London.

Check it out:

http://www.maplin.co.uk/Module.aspx?Mod ... D=&doy=4m4