When the switch is off and your pick up rollers bridge the center rails between main and siding you put track power on Acc which then goes directly to Gnd and your fuse or breaker trips. I went through the same head scratching as described by others above before I finally figured out what was happening. I added relays and all was well and the LEDs worked as I had originally wanted them to.
Follow the advice of the others above. Save yourself the head scratching and use the relays as Stan described his above post!
Cjack posted while I was typing, I have a cheaper version of the same switch from Ebay, but it has the identical problems as shown in Cjacks post above. As I recall the conclusion after discussing this here in the past was that these type of automotive LED switches were all similarly constructed and would cause the same problems.
Woops, I didn't read far enough down, I guess there is one that works properly as per the end of cjack's post above.
