Diagnosing EM score reel problems - PinballHelp.com 

...and it worked! A switch on my Player 3 1000s reel did not open when it was supposed to. Thanks for saving me a lot of time! 😃

Check to make sure that there isn't a scoring switch on the playfield that is stuck closed

@@PinballHelp I figured it out. When I filed the contacts in the 10,000 reel for player 4 they weren't touching anymore so it didn't work so I bent them and messed them up. I bought a reel off of ebay and swapped the contacts over and fixed it. Now I have a problem in the coin door

Yes, this can be a similar situation. The relay thinks it's at the 0 position when it isn't.

@@PinballHelp Thanks! I will subscribe to your channel!

Well... I checked and cleaned all the contacts but it still will not zero for me. When I press the credit button it will just set to another random set of numbers. It doesn't keep clicking like in your video. It appears that most of them only move a number or two. Do you have any other ideas? My brain is fried! Thanks.

I have the same issue with my 72' Gottlieb Grand Slam. If I touch the coil plate for the "Score reset completed" relay it will reset the reels and keep running until a coin is inserted. On rare occasions it will reset when the game starts, but that's super rare. I wish I knew a bit more about my machine. I only have a 1 player machine so it should be easier. I'm new to working on things this old so it's a learning curve. Not that's it's hard, I'm just worried about breaking the machine worse. It plays and I got all the targets working except one pop bumper. At least I can play it, but it would be nice to get an accurate score count for each game play. The machine has 85,754 plays on it so I'm blown away that it's lasted as long as it has.

@@teamhex I don't think that's my issue. If my score reset cam kept running then I would know to check the individual score reels to make sure the contacts are clean and functioning correctly. My problem is that when I press the game start button the score reels do not reset to all zeros. They will only advance one or two numbers. For example: I put them all on ones (1 - 1 - 1 - 1) then press start and they will advance one or two numbers (2 - 2 - 3 - 2). Now... I wonder if this is my problem - Just before this started happening my machine would totally shut down when the score hit 100. The problem was the 100 point chime coil was fried. I simply disconnected the coil and it works great except for the score reels not zeroing. I wonder if it needs the chime coil to complete some scoring reset circuit?

David Rendon yep 600 grit works well.