Hi, I was converting a Piko loco several weeks ago by adding a sound decoder and changing the wiring, yesterday I've added a 4 pin Roco electrical coupling,
having converted it a while ago I've forgot what Aux functions have been already taken, I needed 2 for interior lights, I knew Aux 1 & 2 had been taken for markerlights, 3 & 4 were taken for the designation sign and I thought 5 & 6 was available but these 2 had also been taken for the cab light, Aux 7 was taken for the high beam so there was only one left: Aux 8, from the instruction booklet I took the photo from a 22 pinPlux sound decoder and it stated: from top downwards: Aux 7, Aux 8 and Aux 6, so I soldered the wire to Aux 8 solder pad but nothing happened the interior light didn't come on, I than cross checked the Aux 8 function and it related to the high beam, I thought this is very odd., I than took another instruction booklet and found out the mixed up the order of Aux functions: it should have read: Aux 8, Aux 7 and Aux 6, realizing they've made a printing error I than soldered the wire to the correct solder pad and everything works fine now.,

when you get to my age putting a spanner into the works doesn't help and you think you are getting older than you think you are., after I've discovered the printing error my brain recovered very quickly and I felt much younger again

John