"Please explain the purpose of CV 15 and 16: If I have a train, where is one motorised coach and two or three (or more) coaches with light only, I am using for all of them the same address (long or short). Should I then somehow adjust CV 15 and 16, or do I not need to bother myself, and just leave it as it stands (or how it will be adjustet automatically)?"
Each decoder has a value in CV 16 when it leaves our shop. This value is the key to decoder lock. As you can see on table 5 of the literature that came with your decoder, motorized decoders will have a value of 1 in CV 16 and lighting only decoders will have a value of 3. To utilize decoder lock program CV 15 with the unlocking code from CV 16. That is to say, if you want to program the motor decoder enter 1 into CV 15 and you will only be able to program the mobile decoder. For a lighting only decoder program a value of 3 into CV 15. At its core decoder lock is based on matching the number in CV 15 to the number in CV 16 of the decoder you want to program. If you are using multiple lighting decoders and you want to program them separately you must FIRST edit CV 16 on each of them to give them unique values. Then when you have them in the same train you will be able to access them each seperately for programming by entering the value you chose for CV 16 into CV 15.