Switched 12V Power Feed Options

[touring_style]

Chaps,

We're going to be hammering the motorways of the UK this year on various holidays and the kids need entertaining in the back (to keep them quiet and me sane).

I've got hold of a complete used entertainment system including 2 x headrests with built in monitors, all wring and a PS2 slim to play games and watch DVDs.

I've powered it all up in the house using a 12V supply and it works perfectly.

I'm going to mount the PS2 in the glove box and my plan was to fit the wiring for it this afternoon and to take power from the fuse box above the glove box.

I assumed it would be the same type of fuse box as in my previous E39 - but no.

The E53 version seems to be an enclosed unit - some sort of complicated distribution module with no access to each fuse location wire from the rear; check them out on eBay to see what I mean.

I don't really want to tap off the cigarette lighter as I don't want to overload that circuit when the lighter socket is in use as well - It really needs a dedicated supply.

The torch charging socket supply definitely won't be man enough for the job, that'll be asking for trouble.

Does anyone know if there's a way to utilise the fuse box - I note there are spare fuse locations, are they non accessible for retro fitting?

Any other power source options behind the dash?

I don't want to have to run a supply cable from the battery in the boot - I'm hoping for a more straight forward solution using what already exists behind the dash - preferably the fuse box.

Thanks in advance for any advice.

[X5-D-Sport]

On the E53 diesel, there is the Jump-Start location on the passenger side of the engine bay fire-wall,

Maybe you could tap off that (incl a fuse) & feed power thru the bulkhead thru an existing cable grommet ?

Just a thought........ & there may even be a substantial power feed some place else, like the fuse board in the glove box ?

[chrisn7]

Unless you plan some very heavy consumption via the accessory/cigarette socket, this would be ok, as it is protected by a 25 amp fuse, which is a pretty substantial supply.

My solution is to add a 2/3/4 (select as required) multi accessory socket adaptor to the rear console in the cubby under the drinks holder. A headrest DVD player runs from this. An extension cable runs forward under the edge of the centre console for whatever else you need such as satnav, TPMS charger or for you perhaps a DVD player etc. This leaves the front accessory socket free for USB phone charger

[touring_style]

[quote="X5-D-Sport Salisbury"]
On the E53 diesel, there is the Jump-Start location on the passenger side of the engine bay fire-wall,

Maybe you could tap off that (incl a fuse) & feed power thru the bulkhead thru an existing cable grommet ?

Just a thought........ & there may even be a substantial power feed some place else, like the fuse board in the glove box ?
[/quote]

Thanks for the suggestion X5-D-Sport; it is a good idea but I need a switched source, that would be a permanent live. Could be useful in the future though....

[quote="chrisn7"]
Unless you plan some very heavy consumption via the accessory/cigarette socket, this would be ok, as it is protected by a 25 amp fuse, which is a pretty substantial supply.

My solution is to add a 2/3/4 (select as required) multi accessory socket adaptor to the rear console in the cubby under the drinks holder. A headrest DVD player runs from this. An extension cable runs forward under the edge of the centre console for whatever else you need such as satnav, TPMS charger or for you perhaps a DVD player etc. This leaves the front accessory socket free for USB phone charger
[/quote]

Thanks also to chrisn7. Does anyone know if either the front or rear 12V cigarette lighter sockets are permanent live or switched with the ignition?

[touring_style]

Does anyone have any experience with this sort of thing;

http://www.ebay.co.uk/itm/221754049720

Looks like a good idea in theory, but would it work with the type of fuse box the E53 uses?

[fenj66]

My front cig lighter socket is definitely permanent live. Not sure about others in rear and boot area. Just plug something in and see if its still on when car locked.

[X5Sport]

They are all unswitched.  You'll need to drop the front fuse board and find a switched point, or do the same in the rear.

[touring_style]

[quote="X5Sport"]
They are all unswitched.  You'll need to drop the front fuse board and find a switched point, or do the same in the rear.
[/quote]

But the fuse box isn't like a traditional fuse box with access to each fuse holder from the rear. Its like a distribution box and is a sealed unit.

If I manage to figure out which fuse point is switched how would I access it to tap into if the unit is sealed?

[X5Sport]

The front one above the glovebox is 'get at able'  You have to take the glove box out and then drop the box.  Not ideal in terms of being mechanic 'friendly' due to the awkward angles/contortions needed, but it's what I did on my '05 to run both the tracker and safety camera detector.

[mikem]

I ran ours from the rear cig lighter and added an inline switch from Maplin which I mounted in one of the blanking plates next to the AV plugs. Looks OEM.

[dgm]

[quote="touring_style"]
Does anyone have any experience with this sort of thing;

http://www.ebay.co.uk/itm/221754049720

Looks like a good idea in theory, but would it work with the type of fuse box the E53 uses?
[/quote]

These are great and will work perfectly in the E53.  I've used them in several cars and they are very straightforward to install.

[touring_style]

As the OP I thought I'd add a quick update in case this thread is useful to anyone else looking for a switched power source behind the dash.

I read in other threads that there are unused relay points in the boot that can be used for a 12v feed - I managed to find a similar unused relay slot on the fuse board above the glove box.

Studying which pin does what I used the switched pin location - arrowed in red in the photo below. What you're looking at is the top of the fuse box once its been unscrewed from its mounting points.

I used the earthing point that can be seen behind my hand as well (also arrowed in red).

I hope others might find this information useful, as I have.

I used an in-line fuse holder to give it it's own fuse and its now working perfectly to run two monitors and the PS2.

Longer journeys will no longer be the torturous affair they have been in the past!