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Hi all,

 

About a month ago the car starter to sound 'weaker' whilst starting and after a week or so of not using it, the battery went dead.

 

So I went out a got a new battery, a Bosch silverline, hooked it up to a C-tek tricklecharger and when it was completely full I installed it and all seemed well.

 

Lately it's the same old story: car runs fine but if I leave it for a couple of days the battery goes dead and I have to charge it again.

 

When I measure the voltage across the terminals in the enginebay I get roughly 14 volts with a running engine but it doesn't seem to make a difference if i let the car idle or rev it to 3000 rpm.

 

So it does seem to be charging.

 

There's no light left on anywhere, I took out the light underneath the bonnet just to be sure as well.

 

My turbo is fitted with just the one battery by the way, it doesn't have the auxillary one in the boot.

 

One thing left to add: around the same time my keyless entry and go packed up...??

 

So it seems something is draining the battery but I've no idea what or how to measure it...please help!!

 

Thanks in advance, any help GREATLY appreciated!

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Hi all,

 

About a month ago the car starter to sound 'weaker' whilst starting and after a week or so of not using it, the battery went dead.

 

So I went out a got a new battery, a Bosch silverline, hooked it up to a C-tek tricklecharger and when it was completely full I installed it and all seemed well.

 

Lately it's the same old story: car runs fine but if I leave it for a couple of days the battery goes dead and I have to charge it again.

 

When I measure the voltage across the terminals in the enginebay I get roughly 14 volts with a running engine but it doesn't seem to make a difference if i let the car idle or rev it to 3000 rpm.

 

So it does seem to be charging.

 

There's no light left on anywhere, I took out the light underneath the bonnet just to be sure as well.

 

My turbo is fitted with just the one battery by the way, it doesn't have the auxillary one in the boot.

 

One thing left to add: around the same time my keyless entry and go packed up...??

 

So it seems something is draining the battery but I've no idea what or how to measure it...please help!!

 

Thanks in advance, any help GREATLY appreciated!

 

 

Disconnect the positive battery terminal and connect your multimeter between the cable and the battery while set on milliamps; after about an hour you should see 40-60 mA (normal parasitic drain from the clock, computer, radio, etc.).  If you see more than 60 mA, start pulling the fuses one at a time until the drain drops back into range; that fuse circuit is the source of your problem.

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Thanks, I will do that!

 

Are there common items that cause a drain like mine?

 

It's a huge battery in perfect condition so for that to go empty in a matter of day's something must be draining A LOT of power?

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Thanks, I will do that!

 

Are there common items that cause a drain like mine?

 

It's a huge battery in perfect condition so for that to go empty in a matter of day's something must be draining A LOT of power?

 

Not really, we have seen all sorts of things create drain.  But this process will help you isolate it quickly.

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Sorry to be a dunce but: the red lead of the multimeter between the positive battery terminal and the cable, the black on on the negative terminal of the battery or...?

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For current (Amps) readings multi meters have a fuse inside that allows a reading of up to about 10amps.  That's why you change the leads to the amps holes so the power goes through the fuse.

 

When you have finished doing your battery drain test remember to put the leads on the multi meter back to their normal position for voltage and resistance readings.  If you don't put them back, the next time you take a voltage reading on a battery it will blow the fuse and you will have to open the meter and replace it.

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Thanks for all your help!

 

I've just finished investigations...

 

A couple of fuses were inserted even though those systems are not on the car (anymore)...for example the tyre pressure monitoring system.

After removing those the drain dropped from roughly 300 mA to 150 mA...

 

After locking the car and letting it 'go to sleep' the drain is a steady 150 mA and that doesn't change regardless of whatever fuse I remove...I've removed the two underneath the seat, all of those in the LHD and RHD-side and the ones in the engine bay.

 

So I'm guessing 150 mA is too much but removing fuses don't seem to affect it??

 

Also: the keyless entry and drive packed up around the same time. I noticed that when I touch the door handle the amps go up so the antennas do work!

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Thanks for all your help!

 

I've just finished investigations...

 

A couple of fuses were inserted even though those systems are not on the car (anymore)...for example the tyre pressure monitoring system.

After removing those the drain dropped from roughly 300 mA to 150 mA...

 

After locking the car and letting it 'go to sleep' the drain is a steady 150 mA and that doesn't change regardless of whatever fuse I remove...I've removed the two underneath the seat, all of those in the LHD and RHD-side and the ones in the engine bay.

 

So I'm guessing 150 mA is too much but removing fuses don't seem to affect it??

 

Also: the keyless entry and drive packed up around the same time. I noticed that when I touch the door handle the amps go up so the antennas do work!

 

Some where in the car, something (probably an aftermarket item) is wired in as "always hot", and you need to locate it.  150mA is still three times the drain the car should have.

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That's the thing....it's completely stock! There's nothing but the standard things in the car...

 

There are no chargers plugged in, there have not been any alterations to the musicinstallation...I can't for the life in me think of anything untoward...

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That's the thing....it's completely stock! There's nothing but the standard things in the car...

 

There are no chargers plugged in, there have not been any alterations to the musicinstallation...I can't for the life in me think of anything untoward...

 

Try disconnecting the alternator power lead and see if that drops it.

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