I agree with G-BENZ. Unless you are trying to use the valet key, you should be able to use the key to open the trunk manually.

The feature of the trunk unlocking when you unlock the doors is vacuum driven and that vacuum is powered by an electric pump I understand... So I can see why you might not be able to just press the button and open the trunk, but inserting the key and pressing it while turned should do the trick.

If you should decide to try to charge the battery from the lighter I believe the lighter is off when the ignition key is off so I wouldn't expect any result unless you have the key inserted and on when trying to charge it. Having the switch on might well consume all of the charge and have none left for the battery...

Good Luck!

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02 S500
92 500SL
92 400E (Sold)
87 300E (Sold)
83 300D Turbo (Sold)
75 300D (Sold)
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