I have my first EM, Doodle Bug, and the original cord has been cut off. I want to replace it with a modern cord with a ground. Picture is attached, with the original brown power cord running to a brown wire on the left and a yellow wire on the right. To the left of all this is a green wire marked "ground wire."

I can desolder the old cord and solder the new cord onto the lugs for the brown and yellow wires easily, but I don't understand electricity well enough to know which of the brown and yellow wires is the power and which is the neutral. Also, I assume that I can just solder the ground from the new cord onto the lug for the green wire.

Can someone please tell me if it's a safe option to solder on all three wires from a new cord, and, if so, which cord wire goes to brown and which to yellow? I'm hoping that a Doodle Bug owner will know, or that someone can explain to me how to test the wires for power and neutral (I have a meter, but I'm a novice at using it), or that it doesn't matter which wires go to which, as long as the ground goes to green (a dangerous assumption?). I'd be very grateful for the help.

DB Wiring (resized).jpg

Thanks for the reply. That helps a bit.

Thanks so much for these replies. They are helping me piece things together. More advice is appreciated if anyone has any.

The yellow wire from the schematic indeed goes the 10 amp fuse (then to red, then purple, then the transformer), so that's easy to verify as the power. However, the brown and yellow wires in my Doodle Bug (as pictured at the top of the post) are far from the transformer--they're halfway back in the cabinet--so I still have to figure out which is hot and which is neutral between them. Maybe I can physically trace them to the transformer and figure it that way, but I'm still not sure.

A very helpful suggestion--thanks!

An excellent tip!

So thanks to all of you for this detailed advice, and I'll close out this thread now with an update. Reading the above cautions and consulting with some other pinball friends makes me realize that it won't be wise for me to put in a new power cord on my own. A friend from out of town with EM and electronics experience has agreed to visit sometime and help me get this job done properly. That way we can test the transformer as well, and we can wire the hot side directly to the power switch and ground the cord to the mounting plate. So I'll wait for him to help me, and plan to update this thread with the results.

Again, thanks to all!

Thanks so much for the detailed reply. I did just hook up a new three-pronged plug to the wiring in the first picture: hot to yellow, neutral to brown, and green to ground. Switched on the game and got a light buzzing, but that's it--no GI and no motors running. No fuses blown either. So back to the drawing board, but at least I have power. I'll read up more on grounding as well. My machine also has a marked ground wire at the transformer.

Thanks, mg81. Up to this point I've been disassembling, cleaning, replacing broken parts, and reassembling. Now that I have the power cord in I'm ready to start troubleshooting, and I'm absolutely lousy with a meter--my knowledge stops at fuse testing. Yes, please do come by when you have time and educate me. I replaced the destroyed lock relay, so the lock relay switch stack could be worth a look as well.