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Battery dead/disconnected and the trunk is locked

I closed the trunk on my 2009 BMW 328i after I disconnected the battery. I was trying to change the battery but needed to get more supplies. So, I closed the trunk Now I can’t open the trunk. Any suggestions?The battery is in the trunk.

no key hole i take it is there a way to jump the car under the hood? time to get out the owners book.

I recently bought this car second hand and it didn’t come with the owner’s manual.

Does the rear seat fold down or is there a pass-thru for skis? A BMW-specific forum should provide a way to determine this. I assume there is no key hole in the trunk lid.

Ed B.

There are jump start connections under the hood, with battery power connected you should be able to release the trunk.

The owners manual can be viewed online at the BMW site;

That might not work. The battery is disconnected, therefore the positive cable might be touching ground. Is there not a trunk release on the floor next to the drivers seat?

My battery was recently disconnected and I had to reprogram my windows.
Everything today is controlled by a “body control module”. Generally there’ll be “initialization procedures” that you can do to reprigram your car’s various bodily functions. Call the BMW dealer’s service department and see if they have one for the lock system.

Read your manual, make sure you do not have a keyed access for the trunk, If not can you lower a back seat to access the unlock control, if not you may have to jump the trunk access circuit with properly applied voltage.

If the trunk has a lock that works with an ordinary key, that lock can probably be picked by a locksmith.

I recall a story about a man who was looking at engagement rings at Tiffany’s and was impressed with a particularly grand piece of jewelry. He got the attention of a clerk and mentioned that there was no price on the ring and wondered what it cost. The clerk smirked, “if you need to ask, you can’t afford it.” BMW owners that I have known have indicated that the dealerships service department has the same opinion of their work. An old friend sold his BMW soon after paying $400 for 2 headlight elements and a small cup of coffee.

@asecular If I told you I was a liar all my life would you believe? video to pas the time, I love it

If you’re pretty sure you didn’t leave the positive cable hanging somewhere where it’s touching metal you should be able to hook a jumper battery to the jump start attachments under the hood. That should give you power to open your trunk.

BTW, I don’t have my service information here at home, but I know late model Mercedes need to have the car programmed to the new battery. Might want to check with your info to see if your BMW needs the same.

Can you even get the hood open??

2 xenon bulbs

  • labor
    = 4 bills

Can’t you pick up a jump start battery and connect it up ?

Once a jump battery is connected under the hood, the entire sytem will be ‘‘live’’ and you can work the trunk.

I think this guy has figured it out by now.

Xenon bulbs could easily be over $100 each, especially on a BMW. Daimler probably charges more than that for theirs. I think they’re about $70-$80 each on my Chrysler. Labor seems a bit high, but that’s what you get from a dealer. Overall, he probably overpaid by about $100 vs. having an independent shop do the work. Now if they were plain ol’ halogens, and he paid that, that would be outrageous.

Re the OP’s question, I would use a battery charger and not a “jump battery” This will limit the current flow if there is a short vs. a battery or portable jump starter that could provide hundreds of amps and cause something to burn up or even a fire in the (locked) trunk if the cable is shorted. A battery charger should provide enough energy to use the remote release. Connect it, try the release, and disconnect it immediately.