Question: 12V power socket in the trunk

Old Mar 23, 2019 | 03:52 PM
  #1  
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Question: 12V power socket in the trunk

Good afternoon fellows,

Last night, I installed a dashcam which I ran the power cable to the trunk and plug it into that 12V socket we have by the driver side tail light location. Now I am encountering an issue, the device won’t power off even after car is off & locked for a long time. This device, Thinkware F800, has parking mode which I selected to disable already.

My question is, does that particular power socket supply power continuously even when we shut off the car? Or is it the case that I just happen to have a defective dashcam. I am very concerned because those dashcam devices do not behave in this way on my other cars. They are usually turned off a coupe of minutes after the car is shut & locked. Certainly I don’t want to risk messing up the battery in the car.

Thank you you in advance for any feedbacks and thoughts. Have a nice weekend.
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Old Mar 23, 2019 | 04:17 PM
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Since the power socket was designed for a trickle charger it is live all the time.
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Old Mar 23, 2019 | 04:20 PM
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Just tested it with a continuity tester, and it does have power at all times.

I ended up routing mine like this:

Question: 12V power socket in the trunk-bspmut5.jpg

Question: 12V power socket in the trunk-xlmljrg.jpg
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Old Mar 23, 2019 | 04:51 PM
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Originally Posted by Jim Brady
Since the power socket was designed for a trickle charger it is live all the time.
Originally Posted by Orcbolg
Just tested it with a continuity tester, and it does have power at all times.

I ended up routing mine like this:



Thank you very much guys! Now that I know what to do, I’ll figure out a way to connect it to another socket that doesn’t supply power continuously.
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Old Mar 23, 2019 | 10:45 PM
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Originally Posted by Jim Brady
Since the power socket was designed for a trickle charger it is live all the time.
Please forgive this ignorant question:. I just took delivery of a 2019 AMG GT roadster, which of course comes with a trickle charger. A mechanic at the local MB dealership suggested to only trickle charge using the under hood connection. Is it safe to use the 12V socket in the trunk for the trickle charger?
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Old Mar 23, 2019 | 11:25 PM
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Originally Posted by garymac
Please forgive this ignorant question:. I just took delivery of a 2019 AMG GT roadster, which of course comes with a trickle charger. A mechanic at the local MB dealership suggested to only trickle charge using the under hood connection. Is it safe to use the 12V socket in the trunk for the trickle charger?
when I took delivery few weeks ago, dealer told me if plan to hook it up for long term storage, use the connection port under the hood instead. While if only using the trickle charger for a shorter period of time, out of town for a week or 2, the power socket in the trunk will do the job. Hope this helps.
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Old Mar 24, 2019 | 07:22 AM
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I would love to understand the rational for that.
I suspect there is a fuse on the cig lighter trunk connection.
In theory over a long term that could pop and let your battery go down but otherwise there is no reason that I can think of.
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Old Mar 24, 2019 | 11:16 AM
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The manual states to use the charger specifically with the trunk adapter, and makes no mention of a time frame. I last week took the cover off of my GT R and unplugged the charger from that specific adapter after 4 months and the Li battery was fully charged and the car fired immediately up.

Moral: just do what the manual tells you to do; not some random dealership employee; many of whom have no idea what they’re talking about.

Bish
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Old Mar 24, 2019 | 01:12 PM
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Originally Posted by thebishman
The manual states to use the charger specifically with the trunk adapter, and makes no mention of a time frame. I last week took the cover off of my GT R and unplugged the charger from that specific adapter after 4 months and the Li battery was fully charged and the car fired immediately up.

Moral: just do what the manual tells you to do; not some random dealership employee; many of whom have no idea what they’re talking about.

Bish
very true, I had the same question regarding to if they already have a specific power socket designed for trickle charger use, why do we have to connect it the other way instead. (The MB trickle charger kit does come with an adapter that has 2 clamps)

Interestingly enough, my Porsche dealer told me similar thing for my 911 winter storage, they even gave me a connector with clamps to hook up the port near the battery. All I did for the past couple years was to plug the trickle charger into the cigarette power outlet in the center console, everything has been great until now.
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Old Mar 24, 2019 | 04:18 PM
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Like Bish, I just took my car cover off last night after three months plus. Full charge. Car started right up.

I use only the port in rhe trunk.
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Old Mar 25, 2019 | 06:34 PM
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Originally Posted by garymac
Please forgive this ignorant question:. I just took delivery of a 2019 AMG GT roadster, which of course comes with a trickle charger. A mechanic at the local MB dealership suggested to only trickle charge using the under hood connection. Is it safe to use the 12V socket in the trunk for the trickle charger?
Just like others have said, trickle charger is designed for trunk plug-in charge in fact my Black Series had a similar charging system. . In some MB models cigarette lighter receptacle will not work for charging your battery which is likely what your dealer tech might have been referring to.
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