PKSlice

Ugh, car sat too long and battery is dead. Also I discovered I cannot unlock the trunk with the key - it will NOT turn with the key in the trunk keyhole. The key unlock pushes in nicely, but it will not turn to the unlock position, no matter how much or how little I push the key in (I know you are supposed to place the key into the hole, turn key left to approx. 10 o'clock position, and then push inward to release. I can open the door with the key but not the trunk. Sprayed WD40 into the key hole but no luck, so I cannot access the battery to boost it.


I looked under the hood in hopes of finding +/- terminals but nothing is apparent.


Don't want to take a crowbar to my trunk lid...

ItalianJoe1

I have applied power to the terminals under the wiper cowl area on a W211 to get enough to pop the trunk. It's possible, don't damage your trunk. It's been a while so I don't know exactly what you need to do but there should be a couple power cables under the plastic area back by the wipers. I used a screwdriver in the clamp of a jumper pack on the positive side, then negative to the body as usual. Powered up fine to pop the trunk and such.

PKSlice

Looking everywhere under the hood I don't see anywhere that I can put the positive cable to...

Serndipity

On the both the CLK320 and CLK430, there is a plastic box, located between the windshield washer tank and fuse box. Under it's cover you'll find the hot lead terminal, where you can apply 12 volts to the vehicle electrical system, which should allow opening the trunk, via the center console switch.

Note: This should only be used to supply 12 volts at low current to the electrical system and not used to charge the main vehicle battery.

See http://www.fitzhughmedia.com/MBF/battery.html for more information.

PKSlice

Oh GOD thank you for the precise location of the hot lead. I never would have thought that little tiny plastic box had anything of significance under it. Flipped said cover open, applied juice from a lawn tractor battery, but had to wait a couple of minutes for the trunk switch to work for some reason (lights came on right away). Trunk is open, yanked the battery and am charging it now.