12v Auxiliary Socket permanently live?

[daveenty]

Would anyone happen to know for certain if the 12v socket in the boot is a permanent live with the ignition switched on, or does it power down after a while? This is on a C217

The reason for asking is that I've had a tracking device connected to it since I've had the car, nearly 3 years, and had nothing but trouble with it from the start. Practically every time I use it I'm getting phone calls/emails./messages warning me that the car is being driven without the ignition on. I've so far had two new units fitted, a firmware flash and numerous check over but it's still the same, hopefully up till today.

The latest engineer to call has suggested that the supply may be switching itself off after a certain amount of time, thereby triggering the warnings. This sounds logical to me, and coincides with the warnings only usually happening on longer journeys and not quick trips around the houses. He has now taken the feed from a different source which has been confirmed as being ignition switched and not auxiliary. He also intimated that when they now fit these devices to modern Mercedes, they are taking the live feed directly from the battery due to the complexity of the modern electronics and things powering down.

It would be of assistance if someone could actually confirm that the auxiliary socket does power off after a while of the boot being shut.

 

[Craiglxviii]

Don’t know on a 217. I do know that in our 251 the boot 12V is permanently live, even with ignition off.

 

[Chrishazle]

Don't know on a 217, but am pretty sure that all the 12v sockets scattered around the car, including in the boot area, are ignition switched so dead when key is out. ****** annoying, found out the hard way could not charge a phone while parked at an Hotel overnight!

 

[peterws1957]

Would anyone happen to know for certain if the 12v socket in the boot is a permanent live with the ignition switched on, or does it power down after a while? This is on a C217

The reason for asking is that I've had a tracking device connected to it since I've had the car, nearly 3 years, and had nothing but trouble with it from the start. Practically every time I use it I'm getting phone calls/emails./messages warning me that the car is being driven without the ignition on. I've so far had two new units fitted, a firmware flash and numerous check over but it's still the same, hopefully up till today.

The latest engineer to call has suggested that the supply may be switching itself off after a certain amount of time, thereby triggering the warnings. This sounds logical to me, and coincides with the warnings only usually happening on longer journeys and not quick trips around the houses. He has now taken the feed from a different source which has been confirmed as being ignition switched and not auxiliary. He also intimated that when they now fit these devices to modern Mercedes, they are taking the live feed directly from the battery due to the complexity of the modern electronics and things powering down.

It would be of assistance if someone could actually confirm that the auxiliary socket does power off after a while of the boot being shut.

Dave - could you cobble together a small 12v bulb fed from the socket into the interior and see if it goes out after a while? Just a thought.

 

[daveenty]

I suppose I could do Pete but apparently the problem has now been resolved by using the alternative power source it's now on.

To be honest if it happens again, and especially if they try to charge me again, it will be on it's way to the tip via the dustbin now I know it's location, to be replaced by another model as the insurance still insist upon having one fitted.

 

[mioba]

Have you probed it with a voltmeter. It would be odd that it switches off after sometime as there are things like 12v fridges to go in a boot.
Could it be a loose connection.
I would expect it to be permannt live when the car is running and live when the rear door is open (switched or not).

 

[EmilysDad]

Have you probed it with a voltmeter. It would be odd that it switches off after sometime as there are things like 12v fridges to go in a boot.
Could it be a loose connection.
I would expect it to be permannt live when the car is running and live when the rear door is open (switched or not).

It's not unusual for 12v sockets, in any make of car, to go to seep after a set time after the ignition is switched off.

 

[V6Matty]

It's not unusual for 12v sockets, in any make of car, to go to seep after a set time after the ignition is switched off.

Agree with you there but this is happening when the car is on according to Dave.

 

[daveenty]

Thanks for the replies, unfortunately there's nothing I can do for the next few days as, due to circumstances beyond my control, the car's not going to be going out anywhere so I can't try it. In reality and thinking back, it was always after an hour or two of driving that I used to get the messages from the tracker company which is why a time lapse on the switch seemed to make sense to both myself and the engineer. He determined however that the feed which the unit was getting was not necessarily from the ignition circuit but the auxiliary which could have been the problem, hence his rewiring it to the correct feed.

Could it be a loose connection.

This is also a possibility as the plug which fits into the unit is known to be a poor fit as told to me by the engineer. Unfortunately mine is apparently an earlier type and he didn't have a spare with him, though he did clean and tweak the connectors in the plug to make them a tighter fit.

I'll be attending a meet next weekend (11/12th) in deepest darkest Somerset so will definitely find out on that trip being 4 hours each way.

 

[ajlsl600]

Would anyone happen to know for certain if the 12v socket in the boot is a permanent live with the ignition switched on, or does it power down after a while? This is on a C217

The reason for asking is that I've had a tracking device connected to it since I've had the car, nearly 3 years, and had nothing but trouble with it from the start. Practically every time I use it I'm getting phone calls/emails./messages warning me that the car is being driven without the ignition on. I've so far had two new units fitted, a firmware flash and numerous check over but it's still the same, hopefully up till today.

The latest engineer to call has suggested that the supply may be switching itself off after a certain amount of time, thereby triggering the warnings. This sounds logical to me, and coincides with the warnings only usually happening on longer journeys and not quick trips around the houses. He has now taken the feed from a different source which has been confirmed as being ignition switched and not auxiliary. He also intimated that when they now fit these devices to modern Mercedes, they are taking the live feed directly from the battery due to the complexity of the modern electronics and things powering down.

It would be of assistance if someone could actually confirm that the auxiliary socket does power off after a while of the boot being shut.

My ml is live in rear boot

 

[mioba]

It's not unusual for 12v sockets, in any make of car, to go to seep after a set time after the ignition is switched off.

I was under the impression its when the car is on.

 

[EmilysDad]

I was under the impression its when the car is on.

I've never specifically looked at mine, but as said, some ciggy sockets, on some manufacturers, stay live for a short time after the ignition is turned off.

 

[Alps]

Ive been looking into ignition controlled power sources (opp of what you are on abt), the cigarette socket is indeed something that switches off after a short time, else you have the risk of running the battery down.