how did you hook up the wire..if to 'ground' then a grounded 'electronic /micro' switch will activate it(hence the two wire back to flash board)
just check out the elmod wiring diagram for description of socket
http://www.el-mod.de/pdf/ECO_english.pdf" onclick="window.open(this.href);return false;
I wired my (HL brown/yellow) two wire from the larger 5 wire flash plug directly to a microswitch activated by the mechanical recoil mechanism in my JP. Like stated above, if you jump the HL B/Y two wire plug, the flash will fire. The elmod plug acts as an electronic 'micro switch' to fire the flash in synch with the recoil.
to proove it, just charge the flash and touch the two lead HL plug jumping the wires and the flash fires off.