Hi,

I'm having a problem where trough switch centre and left are activating when the flippers are pressed during switch test.

This only occurs when the switches are closed (i.e. there are balls in the trough). When they are open there is no phantom activation of the trough switches.

I have manually pressed every playfield switch on the same row and column as trough left and trough centre but they do not activate with anything other than the flippers. The activation is only seen for a split second on the DMD but it is causing problems such as 2 balls in the shooter lane and the multiball failing once a ball arrives in the shooter lane, presumably because the phantom trough switch activation is screwing up the machine logic.

Has anyone got any suggestions?

It looks like the outhole switch is missing its diode, where should it go?

IMG_20140418_191703652.jpg

I will give it a go thanks.

I've been looking at the trough switches and I've noticed that they appeared to be wired a bit odd, using the centre trough switch as an example, the green wire is attached to the common lug, the white wire is soldered to the unbranded side of the diode and the other end is soldered to the NO lug.

Its my understanding that the green wire should be on the NO lug, the white on the NC and a diode between NC and COM and the banded side nearest the COM.

Fixed the wiring on the centre trough switch but the problem persists, could the vibration when the flippers are pressed cause a break in contact in the switch itself? Do they go bad in this way?