Originally Posted by otto huber

It will be similar in that the shot off solenoid is actuated by the same valve on the ignition tumbler that is used on a 300SD. The big difference is that your 240D's locks are running off of the same vacuum system as the shut down mechanisms, where as the 300SD locks have their own pump in the trunk.
I had a vacuum leak in one of the door locks of my 240D which was giving me a slow shut down time. I put a golf tee in the line going from the engine compartment to the door locks, and the car shut down quickly.