gpseymour

There's an issue with my 2000 E320 4Matic I've never gotten around to taking care of: the trunk isn't keyed to the same mechanical key as the doors. If I want the trunk lock re-keyed, is this something I have to go to the dealer for? Can it even be done, or will I need to replace all 3 locks (2 doors, plus trunk) with 3 that all match an existing key?

Plutoe

Yes and yes, you use EPC to purchase another lock and key

kajtek1

If your doors have factory key, MB should deliver new trunk tumbler from their key shop in Texas.
Call dealer first to check as not knowing lock history that can be costly.

fabbrisd1

Are you saying this because the rear trunk lock won't budge with your door/key - or are you saying you or prior owner had the locks on both doors replaced/changed without changing trunk key ?

I say this because it is very/very common for the rear trunk lock to "freeze up" from internal corrosion - dissimilar materials/corrosion - and persistent over 2-3 days with repetitive application of PB Blaster - working existing key in/out + pressure right/left (don't break you key) - will eventually free that bad puppy up.

gpseymour

Thanks, I hadn't heard of this. I'll give it a try before I go for a new lock.

fabbrisd1

Please understand from experience - be patient and persistent - over 2/3 days of repeated tries it will seem not to budge - then when you are about to give up - it will free up like nothing every happened.

Each cycle - spray lock with like PB Blaster - work key in-and-out (no turning) spray again - let sit for 30min + - then insert key and to work left/right with firm pressure (don't break key) - repeat cycle again.. and again...and again... then give it one last good spray of PB Blaster for the day ...1and let sit overnight.. start up again the following day...can take 2-3 days but heck it's been "frozen" for a good amount of time..

Check your driver's door lock while you are doing the trunk to make sure it's OK - a decent spray is good there to get the door lock working smooth as well...

kajtek1

Procedure by fabbrisd1 is a good one, although I would question using PBlaster.
It is penetrant with aggressive chemistry, what might leave side effect. Not trying to get experience in the field - I think WD40 is much safer.
Still after they work, all the residue should be cleaned up and graphite apply.