a question re: how switches are wired up

vintagegamer

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If I remember correctly, they are wired in series on a pin, correct? The reason I ask is, on my Time Warp pin I have almost an entire row of targets not working. When I say "row", I'm referring to how they appear in the switch diagram in the manual. They all share one wire color in common (wht/brown) and all but ONE are not working.

I'm thinking if 1 is working, then power is coming from the backbox as it should, but the connection is broken somewhere on the playfield.

Can someone confirm my theory for me?

Thanks!
 
On a pinball machine, switches are wired in a matrix. This is unlike a video game, where all the switches share a common ground. In a pinball machine, imagine a grid of wires - the points at which they intersect are the switches. So, you can have a whole "column" or "row" of switches out. The cause of this can be anything from a bad connection, broken wire, or bad solder joint, to a blown transistor/chip on the board.

The common wire in a column or row of switches is usually daisy chained from switch to switch, so if you have a broken wire near the beginning of the chain, you can have the first switch or two in a column work, but not the rest. Follow the wires, and check continuity with your meter to find the break.

The manual for the pin will have a diagram of the rows/columns of switches in the back, to make troubleshooting easier.

-Ian
 
On a pinball machine, switches are wired in a matrix. This is unlike a video game, where all the switches share a common ground. In a pinball machine, imagine a grid of wires - the points at which they intersect are the switches. So, you can have a whole "column" or "row" of switches out. The cause of this can be anything from a bad connection, broken wire, or bad solder joint, to a blown transistor/chip on the board.

The common wire in a column or row of switches is usually daisy chained from switch to switch, so if you have a broken wire near the beginning of the chain, you can have the first switch or two in a column work, but not the rest. Follow the wires, and check continuity with your meter to find the break.

The manual for the pin will have a diagram of the rows/columns of switches in the back, to make troubleshooting easier.

-Ian

Thanks Ian, yep, that's exactly what I'm looking at is the last 2 pages of the manual that shows the row/column layout. When I am checking for continuity with my DMM on the playfield, do I simply put the red lead on the one wire of a switch in question and the black lead on the other wire? I haven't had to troubleshoot pinball switches in a little while.
 
Not quite sure why this thread was moved out of pinball (as the problem is pinball-specific) but anyway as long as folks can help I guess it doesn't matter where it's at.

According to the post at the below link, clipping one of the connectors of a cap can help resolve a persistent stuck switch error (suggestion comes from member D_Zoot). I am having this problem with the switch test, even though the switch it is pointing to as a problem, works fine in gameplay.

Can someone tell me how I would go about finding which cap they are talking about in the linked post? I've checked the switch on the underside of the playfield and the leaves are not touching except for when the ball pushes the contact points together. However the switch test is saying that this specific switch (#24) is stuck.

http://forum.arcadecontrols.com/index.php?topic=73748.0

Thanks!
 
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Have you checked for continuity on the switch that the manual says is stuck. A visual inspection is not good enough, use your meter. If you find continuity then you need to find the short. My guess is if it is not obvious on the switch then it is the board. Try disconnecting the cab to backbox connector and recheck for continuity at the switch.

If the problem goes away then the problem is isolated to the backbox, almost certainly the board. Each switch has a pair of transistors that may have failed, tracing the circuit with the manual will point out which ones are associated.

With the connectors to the board disconnected test the transistors with the diode function of your meter. You can use the others for reference as to what you are expecting to see. If the transistors in question are shorted then you'll need to replace them. Ed at Great Plains will likely have the parts or a good substitution.
 
Have you checked for continuity on the switch that the manual says is stuck. A visual inspection is not good enough, use your meter. If you find continuity then you need to find the short. My guess is if it is not obvious on the switch then it is the board. Try disconnecting the cab to backbox connector and recheck for continuity at the switch.

If the problem goes away then the problem is isolated to the backbox, almost certainly the board. Each switch has a pair of transistors that may have failed, tracing the circuit with the manual will point out which ones are associated.

With the connectors to the board disconnected test the transistors with the diode function of your meter. You can use the others for reference as to what you are expecting to see. If the transistors in question are shorted then you'll need to replace them. Ed at Great Plains will likely have the parts or a good substitution.

I did not check the voltage on it while in test mode (at least not that I recall) but I know that switch in question is working in gameplay.

I was afraid this thread wasn't specific enough for my issue so I posted the following thread this AM with some further updates:

http://forums.arcade-museum.com/showthread.php?t=189524

It will probably take me a few times of reading this post of yours to make sure I do all of the right things but I will give it a go.
 
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