W208 Convertible-Boot won't open.

[zoffhayward]

Hi all and apologies in advance if this is posted in the wrong place or format. My CLK 430 conv hadn't been used for a couple of months and suffered a flat battery, I got a charged battery and hooked that up to the terminals in the engine compartment to power up the circuits including the boot release, so far, so good, out comes the "carpet" from the boot to connect a standard battery charger which was left until the battery was juiced up. Car starts and drives fine but boot won't open using either fob or switch by gear selector, I cant get either of the "Blade" keys from the fobs more than about 6mm into the lock barrel, I have been squirting WD40 into the barrel for a few days now and getting nowhere, it feels like there is something stopping the key going in rather than it just being full of crud, maybe a pin dropped out of the barrel? Has anyone any ideas or suggestions? I have searched the forums and think I know why the boot isn't opening with switches etc but I'm at a loss as to why the key won't go in the barrel. Thanks Zoff

 

[jaymanek]

The boot should open with the switches unless it thinks its in the locked position with the key or its not closed properly....

Does the soft top all work?

As to the key not going in, thats just a normal case of the lock being totally seized from lack of use.
May have to be drilled and a new lock from MB.

 

[zoffhayward]

Thanks for input, soft top isn't working as I have the plastic luggage area divider down, top latch drops the windows but the hood switch flashes red when you try to operate it, I have tried all the fuses, there all good I wonder if I disturbed some of the wiring to the switch when I took the boot floor liner out to get at the battery?, anyway I have an automotive locksmith due tomorrow, I have been spraying WD40 in with the straw since sunday, the key stops after 7/8 mm as if there is something physical (a previous owners broken key?)in there rather than years of crud!

 

[Dec]

You have about two outcomes to your dilemma;

You get lucky with the WD40 or your locksmith is able to wiggle the key into the lock and open the lock.
Or
The lock has to be drilled out and replaced with new or second hand lock, if the decision to drill the lock is taken, it will be worth first giving the end of the key a whack with a LIGHT hammer, starting with soft taps which get progressively harder until the key enters the lock fully, this may or may not work, but you have nothing to lose if you are intending to drill the lock anyway.

Note, if the key doesn’t fully enter the lock barrel, then it won’t turn, you can make a comparison with the door lock to see exactly how far it needs to enter the lock before it can be turned.

Your problem is that, probably, the first lever (and possibly the second lever) inside the lock barrel is seized in its slot and it is this that is preventing the key blade from entering the lock barrel, the first slot is the one indicated by the green arrow in the picture below, it is located about 11 mm inside the barrel as measured from the keyhole slot.

It’s unlikely that there is anything inside the lock barrel, as you are in possession of both key blades, but if there is a broken key inside the lock then the hammer idea will not work.

This is the same lock barrel that you have in your car, here… Boot lock fix - Mercedes-Benz Owners' Forums

Dec

 

[zoffhayward]

Thanks for the comprehensive reply, your spot on with your assumption, the lovely Mercedes loving guy from Newent Autolocks has just "persuaded" the key past the stuck first blade in the lock barrel, boot now open and strangely all is working fine with the remote and internal releaseswitch, maybe the car decided to only let the boot open with the key as a security measure after flat battery and doors being left ajar for a while? Anyway, thanks for all the help, these forums are fantastic and I wouldn't have been able to run the Mercs we've got/had without all your knowledge

 

[Dec]

The failure of the boot open switch and fob button, at the same time, does come up a lot, as you say it might be a security / locking issue in that the car needs to see the key being turned in the ignition and the boot opened (Light ON) before it resets something, perhaps the central locking vacuum pump.

To prevent a recurrence, flood the lock twice a year with WD40 and work the key in and out and in both rotational directions to keep the lock “fit”.
Always have the boot fully open when you lubricate the lock so as to allow the oil to drain down into all of the lock mechanism.

Dec