Keeps turning itself off when adjusting beam
It sounds like the spring in the tail cap may be depressed which would cause intermittent contact with the negative end of the Batt. Shake the flashlight vigorously, you should NOT hear ANY noise. If you DO, take the end cap off and pull on the spring, you are trying to stretch it out a bit, replace the cap and shake it again. Go through these steps until it is QUIET when you shake it.
Also make sure there's NO CORROSION at the Positive and Negative ends of the contacts.
Maglites are pretty user friendly and the best light money can buy. I have the rechargeable model which I carried for 21 years during my tour in law enforcement.
Anyway, if it still refuses to work properly, go to; www.maglite.com
they are based in California. They will help you get it going. Good luck. :) Read More At : 3 Cell D Blue Flashlight S3D116...