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DISCUSSION => Electrical => Topic started by: manydubs on July 30, 2009, 07:16:47 AM

Title: Trunk access, dead battery
Post by: manydubs on July 30, 2009, 07:16:47 AM

I am trying to get in the trunk to replace a really dead battery.

However I dont have the correct key for the trunk and the central locking system is too dead to unlock the trunk.

I tried charging it up with jump box to positive terminal in engine area, however battery is not good.

So, how can I get into the trunk?  Is there a trick to opening it otherwise?

The car does have a ski-pass...

Title: Trunk access, dead battery
Post by: ak96ss on July 30, 2009, 07:24:26 AM

So putting +12V on the stud in the engine compartment, and grounding to the body, doesn't give you enough juice to open the trunk lock? It should, even with a really dead battery I would think. Hell, you should be able to hook up a battery in the engine compartment like the convertibles...

You could find a child to climb through the ski-pass, but then they would have to know how to open the trunk. Other than that, you could bust out a taillight and get in that way...

Title: Trunk access, dead battery
Post by: DesktopDave on July 30, 2009, 08:57:22 AM

There aren't any tricks to opening the trunk.  If you can get the hood open, connect a charger or car battery to the junction blocks near the right rear to power up the car like ak96ss just described.

Failing that, jack up the front and put positive power to the alternator positive lead.  It's always 'hot' IIRC, that'll give you enough juice to open the car locks.  I can't recall any other positive wires that are always connected.

That trunk is short enough that you might be able to trip the latch with a long screwdriver or something...no need for small children that way (I have two small kids and I can't think of any reward that could make them crawl in there).

Title: Trunk access, dead battery
Post by: rx82000 on April 16, 2011, 04:42:31 PM

Same issue here.

Where is the +12V on the stud in the engine compartment?

Thank you.

Title: Trunk access, dead battery
Post by: DesktopDave on April 16, 2011, 07:25:26 PM

Look on the firewall on the passenger side, above the battery tray (for a 'vert anyway).  There is a plastic cover over a sort of bridge clip.  The very thick positive cable comes through the firewall & into the bridge clip, connected to a lot of smaller wires that head into the conduit across the firewall.

Here's a few pics:

(http://i729.photobucket.com/albums/ww299/desktopdave/318i/th_IMG_3536.jpg) (http://s729.photobucket.com/albums/ww299/desktopdave/318i/?action=view¤t=IMG_3536.jpg)
Taken from the passenger fender...lift that side cover...

(http://i729.photobucket.com/albums/ww299/desktopdave/318i/th_IMG_3537.jpg) (http://s729.photobucket.com/albums/ww299/desktopdave/318i/?action=view¤t=IMG_3537.jpg)
That's the clip I was talking about.  All those wires are +12vdc, some go to the fuse box, others to the starter & alternator.

You can also hook +12vdc to one of the starter terminals or one of the alternator terminals if jumper cables are too short to reach the firewall.  I don't recall which one is correct though.

Title: Trunk access, dead battery
Post by: rx82000 on April 17, 2011, 02:07:09 PM

It worked! Thank you very much for the info.

Title: Trunk access, dead battery
Post by: DesktopDave on April 17, 2011, 03:24:01 PM

I love to hear those words.  I might borrow "It worked" to be my new motto...