1990 Mercedes-Benz 350SDL Q&A
1990 Mercedes-Benz 350SDL Question: Door lock is jammed.
Try lubricating the lock with a penetrating oil like Liquid Wrench. Don't use WD-40 because it's no good in locks, it dries to a waxy substance which is good for rust prevention but it's not really a lubricant, and after a while, it'll gum up a lock. That's my personal painful experience talking... If that's no good, you may need to replace the lock. Get a locksmith to re-key the lock so you can use the original key. - Superbob