M100 percussion zap?

[bourniplus]

Hey guys,
the percussion on my M100 just became intermittent. (works for a minute, then doesn't...) I guess I should mention that a few months ago I replaced the original switch assembly with one from an M3, it's located in place of the left cheekblock, just like on an M3. But this was working fine until today. I just opened the switch assembly to clean and inspect the wiring. No obvious signs of dendrite or anything like that, the switches seem fine.
If I want to try zapping, where should I connect the battery(ies)? I've done it with success to my A100 but can't find anything zapping on a AO29. I was planning to use this organ on a gig tonight, but if it doesn't work I'll use something else...
thanks in advance!
Martin

[enor]

Same procedure as on the A-100, and same terminal on amplifier (terminal K).

[bourniplus]

Thanks again Enor, (I'm the same guy as on the facebook group)
I measured the voltage at terminal K and it was fine (around 30 V going to zero with a key pressed) so I didn't zap. I swapped the percussion tubes with those from my M3, and now everything is fine in both organs. For the moment I can only guess that something is slightly loose or dirty in the tube sockets, and just replacing the tubes helped. I will keep investigating...