I'm trying to troubleshoot a Bally pop bumper (LT Bumper on the schematic) that won't fire. It works on the diagnostic solenoid test, but will not fire when I close the pop bumper switch or short it manually bypassing the diode. Looking at the schematic showed me that it goes back to the MPU on J2-5 AND J2-15. Disconnecting the J2 plug and shorting those two pins does work to fire the coil. Also everything else in the row and column on the switch matrix seem to work.
I am able to trace one side of the switch back to J2-5 and the other side back to J2-15 using continuity test on the multi-meter. But if I jumper the switch closed, bypassing the diode, I don't seem to get continuity when I test J2-5 and J2-15 on the harness plug with the multi-meter. Does this make sense?