My learning curve on this Toledo EM has flattened. I was checking continuity on Cam switch #1D (M-B) and I am getting a a positive continuity test thru O-Blu regardless of the position of the cam and with the blade contacts not touching. R-O does make/break as the Cam rotates. The schematic says #1D O-Blu is the only switch normally closed(pic). I was always of the understanding if a switch was open there should be no circuit, so I began to look for shorts somewhere. I've circled the switch in question and shown via an orange line how I think I am getting a positive test with both blades(O-Blu & Y) removed from the stack and alligator clipped. All other switches in line to Coin Setup Relay were found to be in the state shown on schematic.

This can't be right, or what's the point of #1D being a M-B if O-Blu is getting it's Y from another circuit?

Additionally, by virtue of what I see right below on schematic, is the Lock RE always on?

Thanks for the help.

Cam 1D circuit (resized).jpg

motor Cam 1.pdf

That is a real pearl of info that another Pinsider also shared with me while working on this same machine, and I began using it exclusively over the tone. I should have been clearer, normally I get a reading between .05-.09 ohms on various tests through switches on the motor Cams or maybe from there to a relay. In the case of my " back door" circuit querie/complaint, I measured a 1.1ohm which is plenty low enough for a circuit(?)

The Lock RE has only one switch and that is shown in Pic. It goes to the Game Over RE and based on schematic it's closed until the Lock RE is charged. I could not find the Lock RE anywhere else on schematic.

Ideas?

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