Cigarette lighter always on

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ibashir
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Mon Jul 06, 2020 10:26 pm

Hi. Bought a car USB charger that goes into cigarette lighter to charge the phone. Noticed as I got out that the charger stayed on when I switched the car off.

This would drain the battery?
Anything I can do so that it goes off with the ignition?

TIA
coopman
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Wed Jul 08, 2020 8:12 am

ibashir wrote:
Mon Jul 06, 2020 10:26 pm
Hi. Bought a car USB charger that goes into cigarette lighter to charge the phone. Noticed as I got out that the charger stayed on when I switched the car off.

This would drain the battery?
Anything I can do so that it goes off with the ignition?

TIA
A couple of weeks ago I killed my battery in exactly this way.
ibashir
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Wed Jul 08, 2020 9:10 am

Been thinking about this and it maybe that I will connect the power wire to the lighter to something like the positive to the stereo power. This way when I turn the car off, the lighter with the stereo will get no power.

Just a thought at the moment????? Not sure if this causes any electrical issues?
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HJ1981
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Wed Jul 08, 2020 10:57 am

coopman wrote:
Wed Jul 08, 2020 8:12 am
ibashir wrote:
Mon Jul 06, 2020 10:26 pm
Hi. Bought a car USB charger that goes into cigarette lighter to charge the phone. Noticed as I got out that the charger stayed on when I switched the car off.

This would drain the battery?
Anything I can do so that it goes off with the ignition?

TIA
A couple of weeks ago I killed my battery in exactly this way.
Strange, my USB lighter adapter always switches off when the ignition is off.
Kalimsnor
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Wed Jul 08, 2020 11:27 am

I recently got a voltmeter that goes into the cigarette lighter and noticed that it also stays on even when the ignition is off. Not sure if intended. 325e, 1985.
Moz
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Wed Jul 08, 2020 11:56 am

AFAIR the cigarette lighter is constant 12v. There are other 12v ign lives that you could use such as the radio you mentioned. I ran an extra fused cable direct from the battery alongside my amp wire when installed so I could add a small additional fuesbox for things like this. I took it to the boot though.

Thanks
Everytime you idiot proof something, the world will just give you a bigger idiot.
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Contours
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Wed Jul 08, 2020 2:56 pm

You could maybe remove the charger from the socket!
kdevitt
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Wed Jul 08, 2020 3:53 pm

Pretty certain its a constant 12v too - same as on the E36, lots of people do a bodged electric seat retrofit by just tapping into it. Easiest option as said above is to just remove the socket. If you don't want to do that for some reason, you could always add a switch somewhere.
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davidt
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Wed Jul 08, 2020 6:28 pm

ibashir wrote:
Mon Jul 06, 2020 10:26 pm
Hi. Bought a car USB charger that goes into cigarette lighter to charge the phone. Noticed as I got out that the charger stayed on when I switched the car off.

This would drain the battery?
Anything I can do so that it goes off with the ignition?

TIA
You will find on the auxillary connector a suitable live that will swich off when the ignition is off . https://www.e30zone.net/e30wiki/index.php/Loom.
minesapint
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Wed Jul 08, 2020 8:55 pm

That’s the way they were designed. With ignition switch in position “0” ie, off & without the key inserted, all items of electrical equipment are switched off except.......hazard warning lights, flashers, cigarette lighter, interior lighting, side/parking lights.
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