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Discussion Starter #1
I was trying to find out algorithm how 12v sockets work in Cayman but so far I read controversial information.
Some said it's alive all the time, other that they goes off in 15min, 30min etc. Manual is pretty vague as well.

This is what I think based on my experience. I am using phone charger with LED in glove-box 12v outlet (so I can see if socket is hot or cold) even if I don't charge my phone. Charger circuitry by itself consumes a very little.

Before recently, it was shutting down in 15-30min (doors are closed, alarm not set or set - it does not matter).

Last night I did maintenance on battery (with CTEK charger), so now my battery is 100% full. And as a result 12v outlets stays hot all the time with same conditions. I was waiting for more then 1 hour.

I think that ECU would turn off all or almost all consumers if battery discharged down to certain level. Question, what level we are talking about? 12.6V, 12V or under 12V?

Keep battery not 100% charged will shorten it's life. That's where "smart" CTEK chargers comes to rescue...

Anyway, those guys who said that their equipment goes off when plugged into 12v socket on 981, more likely are taxing on battery charge level, so ECU shut equipment down to prevent any further discharge... And faster it goes off - the lesser charge is in battery or it also may indicate weak battery.

It would be nice if somebody knowledgeable could shed some light on a subject.
 

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My car has entry and drive so it might be different. My experience: The smoking package cigarette lighter socket times out even with a full charged battery. With a battery that needs a charge, CTEK will connect and charge for an unknown to me time frame and time out and disconnect when connected to that socket. The socket in my glove box never times out when used for charging.
 

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Discussion Starter #3
Interesting. Porsche recommends to use cigarette lighter outlet for battery maintenance (someone said because of a thicker wire) and still times out it even when charging?

My 2014 Cayman does not have smoking package, only 3 x 12v outlets (in armrest, glove box and passenger side). I though that I found sensible explanation of that hot/cold sockets behavior but your story continues to baffle me.

When your accessory, plugged into 12v outlet (with time out) goes off, could you measure battery voltage (for experiment sake)?

I'll do it myself (probably have to wait until battery will lose some charge because right now outlets are hot all the time) and post my results.
 

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The CTEK will reawaken the socket when necessary. When it does that/keeps one socket on, the other may stay on too.
If you plug the CTEK in, you can leave it for the winter, as many here do.
 
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Discussion Starter #5
CTEK should measure the battery voltage to see if it is below certain value in order to start charge again BUT if sockets are OFF by ECU command then CTEK will measure 0V and the only way to "reawaken" the socket is to crank the car or open/close door.

But anyway, my question is how/when ECU shut down 12v outlets because on my Cayman, after 100% charge, sockets are hot all the time now.

By the way, I have measured resting voltage of my battery and it's 12.66V.
So, this is 100% and ECU keeps outlets hot all the time. Also, I have measured idle current of phone charger and it's 5mA.
Given battery capacity of 90Ah it will take about 2 years to discharge it using only phone charger in idle mode (theoretical).

Oh well, I will keep looking when ECU will start shutdown sockets again and will measure battery voltage.

The CTEK will reawaken the socket when necessary. When it does that/keeps one socket on, the other may stay on too.
If you plug the CTEK in, you can leave it for the winter, as many here do.
 

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I used the console socket with my Ctek charger, seemed to fine for charging and maintaining a charge... 2013 Boxster
 
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Oh well, I will keep looking when ECU will start shutdown sockets again and will measure battery voltage.
Read the FAQ. Different model but it gives you some idea Cayman Technical Data of parasitic draw,

I would not hold my breath about leaving anything plugged in indefinitely. The AGM batteries are better than the older style batteries in that they only lose about 3% a month. But do a search and read there is a reason people keep a CTEK on their batteries in the winter.

My car has entry and drive so it might be different. My experience: The smoking package cigarette lighter socket times out even with a full charged battery. With a battery that needs a charge, CTEK will connect and charge for an unknown to me time frame and time out and disconnect when connected to that socket. The socket in my glove box never times out when used for charging.
That doesn't sound right. I've had a ctek hooked up for days and some people with 981 keep a ctek hooked up all winter. Are you sure you haven't got that backwards? The cigarette lighter socket never times out.
 

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Thanks for pointing to the interesting information. I like reading facts, technical data and learn something new.

And I am well aware that there are lot's of electrical components which should be active all the time which contributes to the battery drain. Plus some internal discharge, so yes, battery needs to be topped off by trickle charge (if car not driven often) etc.

BUT everybody seemed to miss my original question - with what conditions/when the ECU WILL shutdown 12v sockets...

If you would read my original post, I have an explanation to this behavior (only a logical conclusions, until I will have facts to prop it). And yes, I searched web regarding this and that how I come by planet-9 forum as Porsche owners/enthusiasts community, thinking you guys can shed light on it.

Read the FAQ. Different model but it gives you some idea Cayman Technical Data of parasitic draw,

I would not hold my breath about leaving anything plugged in indefinitely. The AGM batteries are better than the older style batteries in that they only lose about 3% a month. But do a search and read there is a reason people keep a CTEK on their batteries in the winter.
 

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BUT everybody seemed to miss my original question - with what conditions/when the ECU WILL shutdown 12v sockets...
Porsche iManual | 2013 -

The sockets and thus the connected electrical accessories function even if the ignition is switched off or the ignition key is removed.
If the engine is not running and the accessories are switched on, the vehicle battery will be discharged. The power supply is interrupted after 30 minutes to protect the vehicle battery. If the load is to be switched on again, the ignition must be switched on once.
 

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That doesn't sound right. I've had a ctek hooked up for days and some people with 981 keep a ctek hooked up all winter. Are you sure you haven't got that backwards? The cigarette lighter socket never times out.
Don't care how it sounds, that's how it works on my 2015 Boxster GTS with entry and drive. Do you own a 2015 with entry and drive? Didn't think so ...
 

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Discussion Starter #11
I've read manual too. And before I charged battery to 100% I have no question, because my phone charger would eventually be turned off (didn't clock it if it's 15 or 30min).

But now, phone charger stays powered on for hours already...

Porsche iManual | 2013 -

The sockets and thus the connected electrical accessories function even if the ignition is switched off or the ignition key is removed.
If the engine is not running and the accessories are switched on, the vehicle battery will be discharged. The power supply is interrupted after 30 minutes to protect the vehicle battery. If the load is to be switched on again, the ignition must be switched on once.
 

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I assume that battery would have a significant charge after a four hour drive, but when I tried to charge my phone, it would do it only with switch on.


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Well, are you saying that in your vehicle 12v sockets do not stay hot when engine is not running? Btw, what vehicle are you driving?

I assume that battery would have a significant charge after a four hour drive, but when I tried to charge my phone, it would do it only with switch on.


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The general concensus is that the 12 volt sockets remain hot for a variable amount of time (usually about 10 minutes in my case) but I want at least the footwell socket to go off when the ignition key is removed. The reason is that I have a dashcam installed taking power from that socket, and obviously I don't want many minutes of the stationary interior of my garage on video after I get home. Does anyone know if the sockets circuit can be reprogrammed to switch off more quickly? The other option would be a 12 volt adaptor with an on/off switch on the end - the camera adaptor doesn't have such a thing - but that isn't very satisfactory.
 

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I used the glove box power outlet for my IPOD connection and a Battery Tender connected directly to the battery when parked. If I leave it parked for more than week (usually) the IPOD is dead when I get in. Takes about 15 minutes of driving before my IPOD has enough juice to start streaming music again.
 

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Well, are you saying that in your vehicle 12v sockets do not stay hot when engine is not running? Btw, what vehicle are you driving?
Mine is CGTS. I am saying they are not hot when ignition is off.


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I was trying to find out algorithm how 12v sockets work in Cayman but so far I read controversial information.
Some said it's alive all the time, other that they goes off in 15min, 30min etc. Manual is pretty vague as well.

This is what I think based on my experience. I am using phone charger with LED in glove-box 12v outlet (so I can see if socket is hot or cold) even if I don't charge my phone. Charger circuitry by itself consumes a very little.

Before recently, it was shutting down in 15-30min (doors are closed, alarm not set or set - it does not matter).

Last night I did maintenance on battery (with CTEK charger), so now my battery is 100% full. And as a result 12v outlets stays hot all the time with same conditions. I was waiting for more then 1 hour.

I think that ECU would turn off all or almost all consumers if battery discharged down to certain level. Question, what level we are talking about? 12.6V, 12V or under 12V?

Keep battery not 100% charged will shorten it's life. That's where "smart" CTEK chargers comes to rescue...

Anyway, those guys who said that their equipment goes off when plugged into 12v socket on 981, more likely are taxing on battery charge level, so ECU shut equipment down to prevent any further discharge... And faster it goes off - the lesser charge is in battery or it also may indicate weak battery.

It would be nice if somebody knowledgeable could shed some light on a subject.
I may have just discovered this as well. It's confusing because the manual is written to carefully avoid telling you how the system actually works, and because the ambient light level apparently determines how long at least some of the accessories stay powered up (16 minutes in darkness, 1 minute otherwise, according to page 72 of the owner's manual.) But my battery just failed to start the car for the first time after 26 months, and I suspect the shorter-than-normal service life is due to the Valentine 1 that I've wired into the Homelink harness not always turning itself off consistently. Either that or the Atmel controller that I use to retain my PSE and Sport button settings.

The latter only takes 20 mA but the V1 probably sucks down 300 or more. I know I've seen it power itself down after several minutes (or at least an hour or so) but if you're right that may not be a good thing.

So... add at least one anecdote to the pile.

Edit: once the battery voltage goes low enough, the accessory outlets are definitely all turned off. There is even a message to that effect that pops up on the dashboard display. Apparently this is true in both directions; my CTek wouldn't charge/maintain the battery through the smoking-package lighter socket until I hooked up another battery.
 

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Discussion Starter #18
Thanks for sharing your story. Yes, this make sense, when battery voltage is low - ECU will turn outlets off (otherwise always hot).
So, if accessories are not staying on that could be indication of weak battery which needs to be charged or replaced. That was my point in my original post.

Speaking about HomeLink power - I don't know how it suppose to work but 300mA is substantial draw especially for a low mileage car (or if you are driving it everyday by hour or so that should not be a problem).
 
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