(Topic ID: 125624)

TZ - Switch Matrix Issue (FIXED!)

By swedishc

4 years ago

Topic Stats

  • 8 posts
  • 3 Pinsiders participating
  • Latest reply 4 years ago by ChrisHibler
  • Topic is favorited by 1 Pinsider


Linked Games

Topic Gallery

There have been 4 images uploaded to this topic. (View topic image gallery).


#1 4 years ago

I am having an issue with optos on my TZ, and I am having trouble narrowing down the problem.

The issue I am having is with two opto switches (74 - Gumball Popper) and ( 84 - Center Lock). Both are next to each other on the same row (J208-4 White/Yellow).

I re-pinned the J5 connector that goes to the GLM 10 Opto Board with a fresh molex connector, but it still didn't solve the issue. That White/Yellow wire appears to be fine where it connects to both the OSB-10B and J208 on the CPU board.

I just shopped the machine, so there were a lot of worn leaf switches with new diodes I replaced while the playfield was out of the machine. It is totally possible that I screwed something up while changing out all of those diodes, but I can't see any incorrect wiring or diodes going the wrong way.

What makes me think it is a matrix issue is because when I interrupt the opto switch (73 - Right Ramp) which is on the same column as opto switch (74 - Gumball Popper), The gumball popper opto will start working again.

Is there a suspect diode or switch I should test or replace? I included the switch matrix diagram if that helps.


#2 4 years ago

Shot in the dark...
Check the diode on the buy-in button. Make sure it's not backwards or touching a solder lug it shouldn't.

After that, get into switch test again.
Remove the left most switch matrix connector (white and green wires); the one just above the (orange wires) direct switch connector.

Report back.
Chris Hibler - CARGPB #31
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#3 4 years ago

Thanks Chris! You always have good advice.

I didn't know the buy-in button had a diode. I checked behind the switch and didn't see anything out of place.

I tried removing J212 (Cabinet Switches) and the problem optos are now working in switch test. I am not sure why that worked. Any idea what might be causing this?

#4 4 years ago

So what's the issue with 84 center lock?

Are all other switches working as they should?

Are you saying when you interrupt opto 73, opto 74 also activates? If that's the case and you're getting phantom switch closures with the optos, you've likely got a bad LM339 chip on the opto board under the playfield.

#5 4 years ago

never mind......started to post and had a situation pop up before I could send.....didn't see your report back before posting. Good call Chris.

#6 4 years ago

Why thank you sir!

Removing J212 takes the cabinet switches out of the matrix.
I suspected that the buy-in button diode may be the issue since the buy-in button, switch 73, 74, and the always closed switch 24 (which is on the coin door interface board) make a rectangle. Switch matrix problems like this always manifest in a rectangle.

You're buy-in button will have two diodes. One is for the lamp and one is for the switch. In the first picture, you can see the switch diode, with the banded end connected to rear-most lug of the switch.
In the second picture, you can see the white wire is connected closest to the coin door, and the green wire right behind it. The non-banded end of the switch diode connects to the same lug as the white wire.
An additional requirement for the buy-in button to help "cause" this problem is that the buy-in button must be closed, or damaged/miswired in such a way as to appear closed. If the white wire and the green wire conductors were touching on the switch, this would cause the problem.

Chris Hibler - CARGPB #31
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#7 4 years ago

Yup, you were totally right about the buy-in button. I never would have suspected that was at fault.

I still didn't see any diodes for either the light or the switch (see below), but I did notice that I had put the wire on the bottom of the switch on the wrong lug. When I switched it to the other lug the problem totally went away.

I owe you one, Chris. That was such great help!

Promoted items from the Pinside Marketplace
$ 9.95
Playfield - Toys/Add-ons
$ 28.00

Hey there! Got a moment?

Great to see you're enjoying Pinside! Did you know Pinside is able to run thanks to donations from our visitors? Please donate to Pinside, support the site and get anext to your username to show for it! Donate to Pinside